Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 726
Filter
1.
Proc Natl Acad Sci U S A ; 121(24): e2320898121, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38833464

ABSTRACT

The World Health Organization identifies a strong surveillance system for malaria and its mosquito vector as an essential pillar of the malaria elimination agenda. Anopheles salivary antibodies are emerging biomarkers of exposure to mosquito bites that potentially overcome sensitivity and logistical constraints of traditional entomological surveys. Using samples collected by a village health volunteer network in 104 villages in Southeast Myanmar during routine surveillance, the present study employs a Bayesian geostatistical modeling framework, incorporating climatic and environmental variables together with Anopheles salivary antigen serology, to generate spatially continuous predictive maps of Anopheles biting exposure. Our maps quantify fine-scale spatial and temporal heterogeneity in Anopheles salivary antibody seroprevalence (ranging from 9 to 99%) that serves as a proxy of exposure to Anopheles bites and advances current static maps of only Anopheles occurrence. We also developed an innovative framework to perform surveillance of malaria transmission. By incorporating antibodies against the vector and the transmissible form of malaria (sporozoite) in a joint Bayesian geostatistical model, we predict several foci of ongoing transmission. In our study, we demonstrate that antibodies specific for Anopheles salivary and sporozoite antigens are a logistically feasible metric with which to quantify and characterize heterogeneity in exposure to vector bites and malaria transmission. These approaches could readily be scaled up into existing village health volunteer surveillance networks to identify foci of residual malaria transmission, which could be targeted with supplementary interventions to accelerate progress toward elimination.


Subject(s)
Anopheles , Bayes Theorem , Malaria , Mosquito Vectors , Animals , Anopheles/parasitology , Mosquito Vectors/parasitology , Humans , Malaria/transmission , Malaria/epidemiology , Malaria/immunology , Malaria/parasitology , Seroepidemiologic Studies , Insect Bites and Stings/epidemiology , Insect Bites and Stings/immunology , Insect Bites and Stings/parasitology , Sporozoites/immunology
2.
Malar J ; 23(1): 166, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38807105

ABSTRACT

BACKGROUND: Deforestation is an important driver of malaria dynamics, with a relevant impact on mosquito ecology, including larval habitat availability, blood-feeding behaviour, and peak biting time. The latter is one of several entomological metrics to evaluate vectorial capacity and effectiveness of disease control. This study aimed to test the effect of forest cover percentage on the peak biting time of Plasmodium-uninfected and infected Nyssorhynchus darlingi females. METHODS: Mosquitoes were captured utilizing human landing catch (HLC) in the peridomestic habitat in field collections carried out in the wet, wet-dry transition, and dry seasons from 2014 to 2017 in areas with active malaria transmission in Amazonian Brazil. The study locations were in rural settlements in areas with the mean annual malaria parasite incidence (Annual Parasite Incidence, API ≥ 30). All Ny. darlingi females were tested for Plasmodium spp. infection using real time PCR technique. Forest cover percentage was calculated for each collection site using QGIS v. 2.8 and was categorized in three distinct deforestation scenarios: (1) degraded, < 30% forest cover, (2) intermediate, 30-70% forest cover, and (3) preserved, > 70% forest cover. RESULTS: The highest number of uninfected female Ny. darlingi was found in degraded landscape-sites with forest cover < 30% in any peak biting time between 18:00 and 0:00. Partially degraded landscape-sites, with (30-70%) forest cover, showed the highest number of vivax-infected females, with a peak biting time of 21:00-23:00. The number of P. falciparum-infected mosquitoes was highest in preserved sites with > 70% forest cover, a peak biting at 19:00-20:00, and in sites with 30-70% forest cover at 22:00-23:00. CONCLUSIONS: Results of this study show empirically that degraded landscapes favour uninfected Ny. darlingi with a peak biting time at dusk (18:00-19:00), whereas partially degraded landscapes affect the behaviour of Plasmodium-infected Ny. darlingi by shifting its peak biting time towards hours after dark (21:00-23:00). In preserved sites, Plasmodium-infected Ny. darlingi bite around dusk (18:00-19:00) and shortly after (19:00-20:00).


Subject(s)
Feeding Behavior , Forests , Mosquito Vectors , Animals , Brazil , Female , Mosquito Vectors/physiology , Mosquito Vectors/parasitology , Conservation of Natural Resources , Insect Bites and Stings/epidemiology , Seasons , Malaria/transmission
3.
PLoS Negl Trop Dis ; 17(8): e0010831, 2023 08.
Article in English | MEDLINE | ID: mdl-37552669

ABSTRACT

BACKGROUND: Transmission models have a long history in the study of mosquito-borne disease dynamics. The mosquito biting rate (MBR) is an important parameter in these models, however, estimating its value empirically is complex. Modeling studies obtain biting rate values from various types of studies, each of them having its strengths and limitations. Thus, understanding these study designs and the factors that contribute to MBR estimates and their variability is an important step towards standardizing these estimates. We do this for an important arbovirus vector Aedes aegypti. METHODOLOGY/PRINCIPAL FINDINGS: We perform a systematic review using search terms such as 'biting rate' and 'biting frequency' combined with 'Aedes aegypti' ('Ae. aegypti' or 'A. aegypti'). We screened 3,201 articles from PubMed and ProQuest databases, of which 21 met our inclusion criteria. Two broader types of studies are identified: human landing catch (HLC) studies and multiple feeding studies. We analyze the biting rate data provided as well as the methodologies used in these studies to characterize the variability of these estimates across temporal, spatial, and environmental factors and to identify the strengths and limitations of existing methodologies. Based on these analyses, we present two approaches to estimate population mean per mosquito biting rate: one that combines studies estimating the number of bites taken per gonotrophic cycle and the gonotrophic cycle duration, and a second that uses data from histological studies. Based on one histological study dataset, we estimate biting rates of Ae. aegypti (0.41 and 0.35 bite/mosquito-day in Thailand and Puerto Rico, respectively). CONCLUSIONS/SIGNIFICANCE: Our review reinforces the importance of engaging with vector biology when using mosquito biting rate data in transmission modeling studies. For Ae. aegypti, this includes understanding the variation of the gonotrophic cycle duration and the number of bites per gonotrophic cycle, as well as recognizing the potential for spatial and temporal variability. To address these variabilities, we advocate for site-specific data and the development of a standardized approach to estimate the biting rate.


Subject(s)
Aedes , Insect Bites and Stings , Animals , Humans , Mosquito Vectors , Insect Bites and Stings/epidemiology , Thailand/epidemiology , Feeding Behavior
4.
Am J Med ; 136(9): 937-940, 2023 09.
Article in English | MEDLINE | ID: mdl-37355195

ABSTRACT

BACKGROUND: Imported fire ants aggressively sting humans, leading to a variety of local and systemic effects. Fire ants display a behavioral adaptation to survive flooding, called "rafting," bringing humans into even more contact with fire ants. METHODS: To assess frequency of encounters with fire ant rafts, duck hunters on the website "Duck Hunter's Forum" were asked about their experiences with the ants while wading or boating in flooded areas. All members of the group received a brief explanation and asked to respond directly if they had had such an encounter. They were then asked to fill out a short 6-question survey. RESULTS: There were 2021 views of the thread about fire ant raft encounters, with 35 (1.7%) responses. Twenty-four (68.6%) said they had experienced encounters with fire ant rafts. Six responders described purposely or inadvertently physically touching the rafts with their body parts, boat, or a paddle, causing the ants to enter their boat or to climb directly onto the hunter(s). Five respondents were stung (number of stings from "a few" to 50), describing reactions to stings as "small pustules," "whelps," and "pimple-like, puss-filled whelps." CONCLUSIONS: These results confirm that fire ant rafts formed during flooding present a potential hazard to persons walking, wading, or boating in those areas. We suggest that these rafts are an under-appreciated health hazard. It is reasonable to assume that people in flooded areas occasionally contact these floating rafts and are stung multiple times. We provide preliminary prevention/protection recommendations for health professionals, to be shared with their patients and the general public.


Subject(s)
Ant Venoms , Ants , Exanthema , Insect Bites and Stings , Animals , Humans , Insect Bites and Stings/epidemiology , Floods , Ships
5.
Yonsei Med J ; 64(6): 404-412, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37226567

ABSTRACT

PURPOSE: Most bee sting injuries are benign, although sometimes they can result in life threatening outcomes, such as anaphylaxis and death. The purpose of this study was to investigate the epidemiologic status of bee sting injuries in Korea and to identify risk factors associated with severe systemic reactions (SSRs). MATERIALS AND METHODS: Cases were extracted from a multicenter retrospective registry for patients who had visited emergency departments (EDs) for bee sting injuries. SSRs were defined as hypotension or altered mental status upon ED arrival, hospitalization, or death. Patient demographics and injury characteristics were compared between SSR and non-SSR groups. Logistic regression was performed to identify risk factors for bee sting-associated SSRs, and the characteristics of fatality cases were summarized. RESULTS: Among the 9673 patients with bee sting injuries, 537 had an SSR and 38 died. The most frequent injury sites included the hands and head/face. Logistic regression analysis revealed that the occurrence of SSRs was associated with male sex [odds ratio (95% confidence interval); 1.634 (1.133-2.357)] and age [1.030 (1.020-1.041)]. Additionally, the risk of SSRs from trunk and head/face stings was high [2.858 (1.405-5.815) and 2.123 (1.333-3.382), respectively]. Bee venom acupuncture [3.685 (1.408-9.641)] and stings in the winter [4.573 (1.420-14.723)] were factors that increased the risk of SSRs. CONCLUSION: Our findings emphasize the need for implementing safety policies and education on bee sting-related incidents to protect high-risk groups.


Subject(s)
Anaphylaxis , Insect Bites and Stings , Bees , Male , Animals , Insect Bites and Stings/complications , Insect Bites and Stings/epidemiology , Retrospective Studies , Anaphylaxis/epidemiology , Anaphylaxis/etiology , Emergency Service, Hospital , Republic of Korea/epidemiology
6.
Am J Trop Med Hyg ; 108(5): 981-986, 2023 05 03.
Article in English | MEDLINE | ID: mdl-37037437

ABSTRACT

Mosquito-borne diseases are a global burden; however, current methods of evaluating human-mosquito contact rates are expensive and time consuming. Validated surveys of self-reported mosquito bites may be an inexpensive way to determine mosquito presence and bite exposure level in an area, but this remains untested. In this study, a survey of self-reported mosquito bites was validated against household mosquito abundance from six communities in Esmeraldas, Ecuador. From February 2021 to July 2022, households were interviewed monthly, and five questions were used to ask participants how often they were bitten by mosquitoes at different times during the day. At the same time, adult mosquitoes were collected using a Prokopack aspirator. Species were identified and counted. Survey responses were compared with the total number of mosquitoes found in the home using negative binomial regression. More frequent self-reported mosquito bites were significantly associated with higher numbers of collected adult mosquitoes. These associations were driven by the prevalence of the dominant genera, Culex. These results suggest that surveys of perceived mosquito bites relate to actual mosquito presence, making them a potentially useful tool for determining the impact of vector-control interventions on community perceptions of risk but less useful for assessing the risk of nondominant species such as Aedes aegypti. Further work is needed to examine the robustness of these results in other contexts.


Subject(s)
Aedes , Insect Bites and Stings , Adult , Animals , Humans , Self Report , Mosquito Vectors/physiology , Insect Bites and Stings/epidemiology , Ecuador/epidemiology , Family Characteristics , Aedes/physiology
7.
Sci Rep ; 13(1): 5413, 2023 04 03.
Article in English | MEDLINE | ID: mdl-37012274

ABSTRACT

Onchocerciasis is a parasitic disease transmitted by black flies. Human onchocerciasis is a public health and socioeconomic problem in Nigeria. Its prevalence and morbidity have reduced over the years because of control efforts especially, Mass Drug Administration with ivermectin. The current goal is to eliminate the disease transmission by 2030. Understanding the changes in transmission patterns in Cross River State is critical to elimination of onchocerciasis in Nigeria. This study was designed to determine the transmission dynamics of onchocerciasis in Cross River State after over two decades of mass ivermectin distribution in endemic communities. Agbokim, Aningeje, Ekong Anaku and Orimekpang are four endemic communities from three Local Government Areas of the State selected for this study. Transmission indices such as infectivity rates, biting rates and transmission potentials, parity rates and diurnal biting activities were determined. A total of 15,520 adult female flies were caught on human baits, Agbokim (2831), Aningeje (6209), Ekong Anaku (4364) and Orimekpang (2116). A total of 9488 and 5695 flies were collected during the rainy and dry seasons respectively in the four communities studied. The differences in relative abundance among the communities were statistically significant (P < 0.001). Monthly and seasonal fly numbers varied significantly (P < 0.008). There were differences in diurnal biting activities of flies in this study at different hours of the day and different months. The peak monthly biting rates were 5993 (Agbokim, October), 13,134 (Aningeje, October), 8680 (Ekong Anaku, October) and 6120 (Orimekpang, September) bites/person/month while the lowest monthly biting rates were 400 (Agbokim, November), 2862 (Aningeje, August), 1405 (Ekong Anaku, January) and 0.0 (Orimekpang, November and December) bites/person/month. Differences in biting rates among the study communities were significant (P < 0.001). The peak monthly transmission potential in Aningeje was 160 infective bites/person/month in the month of February while the lowest (except for months with no transmission) was 42 infective bites/person/month in the month of April. All other study sites had no ongoing transmission in this study. Transmission studies showed that there is progress toward transmission interruption especially in 3 out of the four studied areas. Molecular O-150 poolscreen studies is required to confirm the true transmission situation in the areas.


Subject(s)
Insect Bites and Stings , Onchocerciasis , Simuliidae , Adult , Animals , Female , Humans , Ivermectin/therapeutic use , Onchocerciasis/drug therapy , Onchocerciasis/epidemiology , Nigeria/epidemiology , Mass Drug Administration , Insect Bites and Stings/epidemiology , Insect Vectors/parasitology , Simuliidae/parasitology
8.
Clin Toxicol (Phila) ; 61(3): 181-185, 2023 03.
Article in English | MEDLINE | ID: mdl-36892552

ABSTRACT

BACKGROUND: The families of Hymenoptera causing commonly poisonous animal stings in Taiwan include Apoidea (bee) and Vespidae (wasp). This study aimed to investigate the epidemiologic, clinical characteristics, and outcomes of the severity of envenomation following wasp or bee stings in Taiwan. METHODS: We conducted a retrospective study by identifying all wasp and bee sting-related envenomation reported to the Taiwan National Poison Control Center between January 2001 and November 2021. Data were reviewed and abstracted by two independent reviewers. We then used ordinal logistic regression analysis to find potential predictors of severe wasp and bee sting-related envenomation. RESULTS: In Taiwan, bee or wasp stings mainly occur in late summer and autumn. A total of 611 patients were reported to the Taiwan National Poison Control Center with 7.5% resulting in severe or fatal envenomation. Four-hundred and forty-one patients were eligible for the final analysis of the predictors of severity. Logistic regression analysis showed that a greater number of stings, being stung by wasps, older age, and stings over the body were significant predictors for greater severity. The systemic effects following wasp and bee sting included anaphylactic reaction, prolongation of activated partial thromboplastin time, rhabdomyolysis, acute kidney injury, and elevated liver enzymes. CONCLUSIONS: Wasps generally inflicted more severe envenomation than bees. Only 7.5% of patients had severe or fatal outcomes. Patients with older age, multiple stings, and/or multiple sites of stings were more likely to have severe outcomes.


Subject(s)
Anaphylaxis , Insect Bites and Stings , Wasps , Bees , Animals , Insect Bites and Stings/epidemiology , Insect Bites and Stings/complications , Taiwan/epidemiology , Retrospective Studies , Anaphylaxis/epidemiology , Anaphylaxis/etiology
9.
ABCS health sci ; 48: e023224, 14 fev. 2023. tab, ilus
Article in English | LILACS | ID: biblio-1518549

ABSTRACT

INTRODUCTION: In Brazil, envenomation by bee sting is a public health problem due to its incidence in all regions of the country, as well as the severity of cases. Despite the medical and sanitary importance, the literature on this topic in Brazil is scarce, in the Northeast region. OBJECTIVE: To describe the epidemiological characteristics of bee stings in Paraíba, in the Northeast region of Brazil, from 2015 to 2019. METHODS: The current study is a descriptive and retrospective epidemiological investigation conducted through the recovery of secondary data made available by the database from the Ministry of Health Notification Information System. RESULTS: A total of 1,151 cases were analyzed, and they were reported during all the months of the period of the study and were more frequent in the regions Agreste and Sertão of the Paraíba. The victims were men aged 20 to 59 years. Most individuals received medical assistance within 3 hours of the incident. The cases were classified as mild and progressed to cure. CONCLUSION: In Paraíba, bee stings have increased in recent years, especially in regions with a semi-arid climate. In addition, this study provides data that may be used in the development of educational health actions to promote the prevention and control of bee stings in this region.


Subject(s)
Humans , Animals , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Bee Venoms , Bees , Insect Bites and Stings/epidemiology , Epidemiology, Descriptive , Retrospective Studies , Health Information Systems
10.
J Assoc Physicians India ; 71(10): 57-63, 2023 Oct.
Article in English | MEDLINE | ID: mdl-38716525

ABSTRACT

Objective: Hymenoptera (bees and wasps) stings are a common health hazard in the tropics, particularly in rural areas. The study was planned to describe the clinical spectrum of patients with Hymenoptera (bees and wasps) stings admitted to a medical college hospital in Himachal Pradesh, India. Materials and methods: This was a hospital-based open cohort prospective study conducted on patients admitted with a history of Hymenoptera (bees and wasps) stings. The study period was 1 year, and patients were recruited using a nonprobability sampling method. Demography, clinical and laboratory data, complications, and outcomes were recorded and analyzed. Systemic allergic reactions were classified according to the British Society for Allergy and Clinical Immunology (BSACI) guidelines. Results: A total of 44 patients (25 males and 19 females) were included in the study. All the patients reported in the warmer months from April to November were stung between 6 am and 8 pm and reported within three from the time of the incident. The most common local symptoms of pain and pruritus were reported by 100 and 31.8% of patients, respectively. Features of systemic envenomation reported were dizziness, nausea, vomiting, decreased urine output, hematuria and cola-colored urine, pain abdomen, cough, and wheezing. On examination, local redness and swelling were observed at 100 and 72.7%, respectively. The size of swellings was <10 cm in all of the patients. As per BSACI guidelines, the severity of systemic allergic reactions was mild, moderate, and severe in 70.4, 13.6, and 15.9%, respectively. Transaminases were observed in 40.9% of patients. Acute kidney injury (AKI) developed in 22.7% of patients. The mortality was 4.5% in this study. Conclusion: This is one of the largest studies on Hymenoptera envenomation in India and contributes to our understanding of the subject. How to cite this article: KP MS, Raina S, Kaul R, et al. Clinical Spectrum of Patients Admitted with Hymenoptera (Bees and Wasps) Stings in a Medical College Hospital of Himachal Pradesh, India. J Assoc Physicians India 2023;71(10):57-63.


Subject(s)
Insect Bites and Stings , Humans , Male , Female , India/epidemiology , Adult , Prospective Studies , Animals , Insect Bites and Stings/complications , Insect Bites and Stings/epidemiology , Middle Aged , Hymenoptera , Young Adult , Adolescent , Wasps
11.
PLoS One ; 17(11): e0276783, 2022.
Article in English | MEDLINE | ID: mdl-36374859

ABSTRACT

Malaria vector control interventions in Sumba, Indonesia, have not been able to eliminate malaria. Human drivers of exposure to Anopheles bites were investigated as part of a larger clinical trial evaluating the impact of a spatial repellent product on malaria incidence. Human behavioral observations (HBOs) evaluating temporal and spatial presence, sleeping behaviors, and insecticide treated net (ITN) use, were collected parallel to entomological collections-indoor and outdoor human landing catches (HLCs), and house hold surveys. Data demonstrates that mosquito access to humans, enabled by structurally open houses, is evident by the similar entomological landing rates both inside and outside households. The presence of animals inside houses was associated with increased mosquito entry-however, the number of humans present inside houses was not related to increased mosquito landing. Analyzing mosquito landing rates with human behavior data enables the spatial and temporal estimation of exposure to Anopheles bites, accounting for intervention (ITN) presence and usage. Human behavior adjusted exposure to Anopheles bites was found to be highest in the early in the evening, but continued at lower levels throughout the night. Over the night, most exposure (53%) occurred when people were indoors and not under the protection of nets (asleep or awake) followed by exposure outside (44%). Characterized gaps in protection are outdoor exposure as well as exposure indoors-when awake, and when asleep and not using ITNs. Interestingly, in the primary trial, even though there was not a significant impact of the spatial repellent on vector biting rates by themselves (16%), when factoring in human behavior, there was approximately 28% less exposure in the intervention arm than in the placebo arm. The treated arm had less human behavior adjusted bites in all spaces evaluated though there was proportionally higher exposure indoors. This analysis points to the importance of using HBOs both towards understanding gaps in protection as well as how interventions are evaluated. To mitigate ongoing transmission, understanding context specific spatial and temporal exposure based on the interactions of vectors, humans and interventions would be vital for a directed evidence-based control or elimination strategy.


Subject(s)
Anopheles , Insect Bites and Stings , Insect Repellents , Insecticides , Malaria , Humans , Animals , Malaria/epidemiology , Malaria/prevention & control , Mosquito Control , Indonesia/epidemiology , Mosquito Vectors , Insect Bites and Stings/epidemiology , Insect Repellents/pharmacology , Insecticides/pharmacology , Feeding Behavior
12.
PLoS One ; 17(10): e0276437, 2022.
Article in English | MEDLINE | ID: mdl-36301860

ABSTRACT

BACKGROUND: The level of human exposure to arbovirus vectors, the Aedes mosquitoes, is mainly assessed by entomological methods which are labour intensive, difficult to sustain at a large scale and are affected if transmission and exposure levels are low. Alternatively, serological biomarkers which detect levels of human exposure to mosquito bites may complement the existing epidemiologic tools as they seem cost-effective, simple, rapid, and sensitive. This study explored human IgG responses to an Aedes mosquito salivary gland peptide Nterm-34kDa in Lower Moshi, a highland area with evidence of circulating arboviruses and compared the Aedes IgG responses to Anopheles mosquitoes' salivary antigen (GSG6-P1) IgG responses. METHODS: Three cross-sectional surveys were conducted in 2019: during the first dry season in March, at the end of the rainy season in June and during the second dry season in September in five villages located in Lower Moshi. Blood samples were collected from enrolled participants above six months of age (age span: 7 months to 94 years) and analysed for the presence of anti-Nterm-34kDa IgG antibodies. Possible associations between Nterm-34kDa seroprevalence and participants' characteristics were determined. Levels of IgG responses and seroprevalence were correlated and compared to the already measured IgG responses and seroprevalence of Anopheles mosquitoes' salivary antigen, GSG6-P1. RESULTS: During the first dry season, Nterm-34kDa seroprevalence was 34.1% and significantly increased at the end of the rainy season to 45.3% (Chi square (χ2) = 6.42 p = 0.011). During the second dry season, the seroprevalence significantly declined to 26.5% (χ2 = 15.12 p<0.001). During the rainy season, seroprevalence was significantly higher among residents of Oria village (adjusted odds ratio (AOR) = 2.86; 95% CI = 1.0-7.8; p = 0.041) compared to Newland. Moreover, during the rainy season, the risk of exposure was significantly lower among individuals aged between 16 and 30 years (AOR = 0.25; 95% CI = 0.1 = 0.9; p = 0.036) compared to individuals aged between 0 and 5 years. There was weak to moderate negative correlation between N-term 34kDa IgG and gSG6-P1 antigens. N-term 34kDa seroprevalence were higher compared to gSG6-P1 seroprevalence. CONCLUSION: The findings of this study support that IgG antibody responses towards the Aedes mosquito salivary peptide Nterm-34kDa are detectable among individuals living in lower Moshi and vary with season and geographical area. More individuals are exposed to Aedes mosquito bites than Anopheles mosquito and those exposed to Aedes bites are not necessarily exposed to Anopheles mosquitoes.


Subject(s)
Aedes , Anopheles , Immunoglobulin G , Insect Bites and Stings , Insect Proteins , Salivary Proteins and Peptides , Adolescent , Adult , Animals , Child, Preschool , Humans , Infant , Young Adult , Cross-Sectional Studies , Insect Bites and Stings/epidemiology , Insect Proteins/immunology , Mosquito Vectors , Salivary Proteins and Peptides/immunology , Seroepidemiologic Studies , Tanzania/epidemiology , Child , Middle Aged , Aged , Aged, 80 and over
13.
PeerJ ; 10: e13865, 2022.
Article in English | MEDLINE | ID: mdl-36101880

ABSTRACT

Background: Whilst the human landing catch (HLC) technique is considered the 'gold standard' for estimating human-biting rates, it is labor-intensive and fraught with potential risk of exposure to infectious mosquito bites. This study evaluated the feasibility and performance of an alternative method, the human double net trap (HDNT) relative to HLC for monitoring host-seeking malaria vectors of the Anopheles minimus complex in a semi-field system (SFS). Methods: HDNT and HLC were positioned in two rooms, 30 m apart at both ends of the SFS. Two human volunteers were rotated between both traps and collected released mosquitoes (n = 100) from 6:00 pm till 6:00 am. Differences in Anopheles mosquito densities among the trapping methods were compared using a generalized linear model based on a negative binomial distribution. Results: There were 82.80% (2,136/2,580) of recaptures of wild-caught and 94.50% (2,835/3,000) of laboratory-reared mosquitoes that were molecularly identified as An. harrisoni and An. minimus, respectively. Mean density of An. harrisoni was significantly lower in HNDT (15.50 per night, 95% CI [12.48-18.52]) relative to HLC (25.32 per night (95% CI [22.28-28.36]), p < 0.001). Similarly, the mean density of a laboratory strain of An. minimus recaptured in HDNT was significantly lower (37.87 per night, 95% CI [34.62-41.11]) relative to HLC (56.40 per night, 95% CI [55.37-57.43]), p < 0.001. Relative sampling efficiency analysis showed that HLC was the more efficient trap in collecting the An. minimus complex in the SFS. Conclusion: HDNT caught proportionately fewer An. minimus complex than HLC. HDNT was not sensitive nor significantly correlated with HLC, suggesting that it is not an alternative method to HLC.


Subject(s)
Anopheles , Insect Bites and Stings , Malaria , Animals , Humans , Anopheles/physiology , CD40 Ligand , Entomology/methods , Malaria/epidemiology , Mosquito Vectors , Thailand/epidemiology , Insect Bites and Stings/epidemiology
14.
Front Immunol ; 13: 907424, 2022.
Article in English | MEDLINE | ID: mdl-35693761

ABSTRACT

In the endemic variants of pemphigus foliaceus (PF), in Brazil and Tunisia, patients generate pathogenic IgG4 anti-desmoglein 1 autoantibodies. Additionally, these patients possess antibodies against salivary proteins from sand flies that react with Dsg1, which may lead to skin disease in susceptible individuals living in endemic areas. This minireview focuses on recent studies highlighting the possible role of salivary proteins from Lutzomyia longipalpis (L. longipalpis) in EPF from Brazil and Phlebotomus papatasi (P. papatasi) in EPF from Tunisia. We will briefly discuss the potential mechanisms of molecular mimicry and epitope spreading in the initiation and development of endemic PF (EPF) in Brazil and Tunisia.


Subject(s)
Autoimmune Diseases , Insect Bites and Stings , Pemphigus , Psychodidae , Animals , Desmoglein 1 , Humans , Insect Bites and Stings/epidemiology , Pemphigus/epidemiology
15.
Rev. Ciênc. Méd. Biol. (Impr.) ; 21(1): 73-78, maio 05,2022. fig, tab
Article in English | LILACS | ID: biblio-1370699

ABSTRACT

Introduction: envenomation and deaths by bee stings have increased in all regions of Brazil. However, there are few epidemiological studies on them, especially in the states of northeastern Brazil. Objective: to determine the epidemiological characteristics of bee stings in the state of Bahia, Northeastern Brazil, from 2010 to 2019. Methodology: this is a descriptive and analytical epidemiological study conducted through a retrospective survey of secondary data provided by the database of the Notifiable Diseases Information System of the Ministry of Health. Results: between 2010 and 2019, a total of 7,979 cases were analyzed. Incidents were distributed in 356 municipalities, with the highest frequency in the regions of Agreste and Sertão da Bahia. Cases occurred in all months of the investigated years, with a greater occurrence in urban areas, affecting mainly adult men. The anatomical region of the body most affected by the sting was the head and most cases received medical care within 3 hours after the incident. Local manifestations were more frequent than systemic ones. The injuries were predominantly classified as mild and progressed to cure. Conclusions: the high number of cases and their extensive spatial distribution reveal that bee stings may be considered an emerging and neglected public health problem in the state of Bahia.


Introdução: os acidentes e os óbitos causados por picada de abelha têm aumentado em todas as regiões do Brasil. Contudo, existem poucos estudos epidemiológicos sobre acidentes com abelha, principalmente nos estados do Nordeste do Brasil. Objetivo:determinar as características epidemiológicas do acidente por picada de abelha no estado da Bahia, Nordeste do Brasil, de 2010 a 2019. Metodologia: trata-se de um estudo epidemiológico descritivo e analítico realizado por meio de uma pesquisa retrospectiva de dados secundários disponibilizados pelo banco de dados do Sistema de Informação de Agravos de Notificação do Ministério da Saúde. Resultados: entre 2010 e 2019, um total de 7.979 casos foi analisado. Os acidentes foram distribuídos em 356 municípios, com a maior frequência nas regiões do Agreste e do Sertão da Bahia. Os casos ocorreram em todos os meses dos anos investigados, com maior ocorrência em áreas urbanas, afetando principalmente homens adultos. A região anatômica do corpo mais atingida pela picada foi a cabeça e a maioria dos casos recebeu assistência médica até 3 horas após o incidente. As manifestações locais foram mais frequentes do que as sistêmicas. Os agravos foram predominantemente classificados como leve e progrediram para a cura. Conclusões: o elevado número de casos e a sua extensa distribuição espacial revelam que o acidente causado por picada de abelha pode ser considerado um emergente negligenciado problema de saúde pública no estado da Bahia.


Subject(s)
Humans , Animals , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Bees , Insect Bites and Stings/epidemiology , Brazil/epidemiology , Epidemiologic Factors , Retrospective Studies
16.
Article in English | MEDLINE | ID: mdl-35409999

ABSTRACT

BACKGROUND: Allergic reactions to Hymenoptera stings can have varying levels of severity, according to the Müller grading system. METHODS: By an epidemiological concept, this is a retrospective cohort study. The observed cohort was represented by patients referred to the University Clinic Golnik due to Hymenoptera allergic reaction in the period from 1997 to 2015. From the immunological database of the University Clinic Golnik, we obtained laboratory data (sIgE, skin tests and basophil activation test). The clinical characteristics of patients were obtained from BIRPIS. With the help of a questionnaire, which was sent to each patient in the period from May 2019 to April 2021, we obtained epidemiological data. For the assessment of the association between the severity of allergic reaction for the observed outcome, the severity of the first allergic reaction after Hymenoptera sting was used. Other variables were grouped according to risk factors. DISCUSSION: We will identify the risk factors that could play an important role in a severe systemic reaction: the aetiology of the Hymenoptera sting, sex, age, history and severity of previous systemic reactions, being re-stung in an interval of two months, the frequency of re-stings, atopy, genetic predisposition, preventive medication use, other medication use, beekeeping or living next to beehives and why immunotherapy was not taken. Laboratory data will also be analysed to determine if there is any association with laboratory tests and the severity of the allergic reactions after Hymenoptera stings. CONCLUSIONS: Several new approaches are introduced in the study design. The most important is that the protocol covers epidemiological data gained from the questionnaire, as well as clinical data gained from the Immunological database and BIRPIS database. We expect to obtain significant results that will explain the risk factors for the natural history of Hymenoptera sting allergic reactions and will help allergologists, as well as general doctors, when facing those patients allergic to Hymenoptera venom without immunotherapy.


Subject(s)
Arthropod Venoms , Hymenoptera , Hypersensitivity , Insect Bites and Stings , Adult , Animals , Arthropod Venoms/adverse effects , Humans , Hypersensitivity/epidemiology , Infant , Insect Bites and Stings/epidemiology , Retrospective Studies
17.
Allergol Immunopathol (Madr) ; 50(2): 58-64, 2022.
Article in English | MEDLINE | ID: mdl-35257546

ABSTRACT

OBJECTIVE: The objective of this study was to list the social vespids occurring in Spain, determine their presence in each region, and correlate the data with the vespids responsible for allergic reactions and their progression over time. METHODS: Insects distribution data were collected in two phases: from the southern half of Spain (2008-2012), and from the northern half of Spain (2016-2019). Data for the vespids were collected from the prescriptions of Hymenoptera venom immunotherapy (HVIT) at six Spanish hospitals in the years 2009 and 2019. RESULTS: Polistes dominula and Vespula germanica were the most widely distributed species. Vespa velutina was found to be present in a large part of northern Spain. During the 10 year period, the prescriptions of vespid VIT increased by 42.63%. The north of Spain saw a 3.61 fold greater predominance of prescriptions for Vespula (to some extent influenced by Vespa velutina allergy) whereas in central and southern Spain, there was a 3.97 fold greater predominance of prescriptions for Polistes. CONCLUSIONS: It is the first study that compares the vespid distribution maps with VIT prescription. A noteworthy finding is the wide presence of Polistes dominula and Vespula germanica in Spain and the appearance of Vespa velutina allergy in the northern part of the country. Data of HVIT prescriptions reflect inter-regional variability with the predominance of Vespula (due to Vespula and Vespa) in the north and that of Polistes in the center and south of Spain.


Subject(s)
Hypersensitivity , Insect Bites and Stings , Wasps , Animals , Desensitization, Immunologic , Humans , Hypersensitivity/epidemiology , Hypersensitivity/therapy , Insect Bites and Stings/epidemiology , Insect Bites and Stings/therapy , Spain/epidemiology , Wasp Venoms
18.
Allergol. immunopatol ; 50(2): 58-64, mar. 03, 2022. ilus, graf
Article in English | IBECS | ID: ibc-203103

ABSTRACT

Objective The objective of this study was to list the social vespids occurring in Spain, determine their presence in each region, and correlate the data with the vespids responsible for allergic reactions and their progression over time.Methods Insects distribution data were collected in two phases: from the southern half of Spain (2008–2012), and from the northern half of Spain (2016–2019). Data for the vespids were collected from the prescriptions of Hymenoptera venom immunotherapy (HVIT) at six Spanish hospitals in the years 2009 and 2019.Results Polistes dominula and Vespula germanica were the most widely distributed species. Vespa velutina was found to be present in a large part of northern Spain. During the 10 year period, the prescriptions of vespid VIT increased by 42.63%. The north of Spain saw a 3.61 fold greater predominance of prescriptions for Vespula (to some extent influenced by Vespa velutina allergy) whereas in central and southern Spain, there was a 3.97 fold greater predominance of prescriptions for Polistes.Conclusions It is the first study that compares the vespid distribution maps with VIT prescription. A noteworthy finding is the wide presence of Polistes dominula and Vespula germanica in Spain and the appearance of Vespa velutina allergy in the northern part of the country. Data of HVIT prescriptions reflect inter-regional variability with the predominance of Vespula (due to Vespula and Vespa) in the north and that of Polistes in the center and south of Spain (AU)


Subject(s)
Humans , Animals , Hypersensitivity/epidemiology , Hypersensitivity/therapy , Insect Bites and Stings/epidemiology , Insect Bites and Stings/therapy , Wasp Venoms , Wasps , Desensitization, Immunologic , Spain/epidemiology , Prospective Studies
19.
PLoS Negl Trop Dis ; 16(1): e0010108, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35020729

ABSTRACT

BACKGROUND: In onchocerciasis endemic areas in Africa, heterogenous biting rates by blackfly vectors on humans are assumed to partially explain age- and sex-dependent infection patterns with Onchocerca volvulus. To underpin these assumptions and further improve predictions made by onchocerciasis transmission models, demographic patterns in antibody responses to salivary antigens of Simulium damnosum s.l. are evaluated as a measure of blackfly exposure. METHODOLOGY/PRINCIPAL FINDINGS: Recently developed IgG and IgM anti-saliva immunoassays for S. damnosum s.l. were applied to blood samples collected from residents in four onchocerciasis endemic villages in Ghana. Demographic patterns in antibody levels according to village, sex and age were explored by fitting generalized linear models. Antibody levels varied between villages but showed consistent patterns with age and sex. Both IgG and IgM responses declined with increasing age. IgG responses were generally lower in males than in females and exhibited a steeper decline in adult males than in adult females. No sex-specific difference was observed in IgM responses. CONCLUSIONS/SIGNIFICANCE: The decline in age-specific antibody patterns suggested development of immunotolerance or desensitization to blackfly saliva antigen in response to persistent exposure. The variation between sexes, and between adults and youngsters may reflect differences in behaviour influencing cumulative exposure. These measures of antibody acquisition and decay could be incorporated into onchocerciasis transmission models towards informing onchocerciasis control, elimination, and surveillance.


Subject(s)
Antibodies/blood , Insect Bites and Stings/epidemiology , Saliva/immunology , Simuliidae/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Child , Child, Preschool , Female , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Insect Vectors/immunology , Insect Vectors/parasitology , Male , Middle Aged , Onchocerca volvulus/growth & development , Onchocerciasis/epidemiology , Onchocerciasis/transmission , Simuliidae/parasitology , Young Adult
20.
Parasit Vectors ; 15(1): 11, 2022 Jan 08.
Article in English | MEDLINE | ID: mdl-34996508

ABSTRACT

BACKGROUND: Malaria is transmitted when infected Anopheles mosquitoes take a blood meal. During this process, the mosquitoes inject a cocktail of bioactive proteins that elicit antibody responses in humans and could be used as biomarkers of exposure to mosquito bites. This study evaluated the utility of IgG responses to members of the Anopheles gambiae D7 protein family as serological markers of human-vector contact. METHODS: The D7L2, D7r1, D7r2, D7r3, D7r4 and SG6 salivary proteins from An. gambiae were expressed as recombinant antigens in Escherichia coli. Antibody responses to the salivary proteins were compared in Europeans with no prior exposure to malaria and lifelong residents of Junju in Kenya and Kitgum in Uganda where the intensity of malaria transmission is moderate and high, respectively. In addition, to evaluate the feasibility of using anti-D7 IgG responses as a tool to evaluate the impact of vector control interventions, we compared responses between individuals using insecticide-treated bednets to those who did not in Junju, Kenya where bednet data were available. RESULTS: We show that both the long and short forms of the D7 salivary gland antigens elicit a strong antibody response in humans. IgG responses against the D7 antigens reflected the transmission intensities of the three study areas, with the highest to lowest responses observed in Kitgum (northern Uganda), Junju (Kenya) and malaria-naïve Europeans, respectively. Specifically, the long form D7L2 induced an IgG antibody response that increased with age and that was lower in individuals who slept under a bednet, indicating its potential as a serological tool for estimating human-vector contact and monitoring the effectiveness of vector control interventions. CONCLUSIONS: This study reveals that D7L2 salivary antigen has great potential as a biomarker of exposure to mosquito bites and as a tool for assessing the efficacy of vector control strategies such as bednet use.


Subject(s)
Anopheles/chemistry , Insect Bites and Stings/epidemiology , Nerve Tissue Proteins/immunology , Salivary Proteins and Peptides/chemistry , Adolescent , Animals , Anopheles/physiology , Biomarkers/chemistry , Child , Child, Preschool , Cohort Studies , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin G/blood , Infant , Insect Bites and Stings/diagnosis , Kenya , Nerve Tissue Proteins/chemistry , Salivary Proteins and Peptides/immunology
SELECTION OF CITATIONS
SEARCH DETAIL
...