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1.
Proc Natl Acad Sci U S A ; 119(35): e2122851119, 2022 08 30.
Article in English | MEDLINE | ID: covidwho-2001002

ABSTRACT

Disease transmission prediction across wildlife is crucial for risk assessment of emerging infectious diseases. Susceptibility of host species to pathogens is influenced by the geographic, environmental, and phylogenetic context of the specific system under study. We used machine learning to analyze how such variables influence pathogen incidence for multihost pathogen assemblages, including one of direct transmission (coronaviruses and bats) and two vector-borne systems (West Nile Virus [WNV] and birds, and malaria and birds). Here we show that this methodology is able to provide reliable global spatial susceptibility predictions for the studied host-pathogen systems, even when using a small amount of incidence information (i.e., [Formula: see text] of information in a database). We found that avian malaria was mostly affected by environmental factors and by an interaction between phylogeny and geography, and WNV susceptibility was mostly influenced by phylogeny and by the interaction between geographic and environmental distances, whereas coronavirus susceptibility was mostly affected by geography. This approach will help to direct surveillance and field efforts providing cost-effective decisions on where to invest limited resources.


Subject(s)
Animals, Wild , Communicable Diseases, Emerging , Disease Susceptibility , Animals , Animals, Wild/parasitology , Animals, Wild/virology , Bird Diseases/epidemiology , Bird Diseases/transmission , Chiroptera/virology , Communicable Diseases, Emerging/epidemiology , Communicable Diseases, Emerging/transmission , Communicable Diseases, Emerging/veterinary , Coronavirus , Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Coronavirus Infections/veterinary , Databases, Factual , Environment , Epidemiological Monitoring , Geography , Host-Pathogen Interactions , Incidence , Machine Learning , Malaria/epidemiology , Malaria/transmission , Malaria/veterinary , Phylogeny , Risk Assessment , West Nile Fever/epidemiology , West Nile Fever/transmission , West Nile Fever/veterinary , West Nile virus
2.
Malar J ; 20(1): 475, 2021 Dec 20.
Article in English | MEDLINE | ID: covidwho-1635854

ABSTRACT

BACKGROUND: In March 2020, the government of Uganda implemented a strict lockdown policy in response to the COVID-19 pandemic. Interrupted time series analysis (ITSA) was performed to assess whether major changes in outpatient attendance, malaria burden, and case management occurred after the onset of the COVID-19 epidemic in rural Uganda. METHODS: Individual level data from all outpatient visits collected from April 2017 to March 2021 at 17 facilities were analysed. Outcomes included total outpatient visits, malaria cases, non-malarial visits, proportion of patients with suspected malaria, proportion of patients tested using rapid diagnostic tests (RDTs), and proportion of malaria cases prescribed artemether-lumefantrine (AL). Poisson regression with generalized estimating equations and fractional regression was used to model count and proportion outcomes, respectively. Pre-COVID trends (April 2017-March 2020) were used to predict the'expected' trend in the absence of COVID-19 introduction. Effects of COVID-19 were estimated over two six-month COVID-19 time periods (April 2020-September 2020 and October 2020-March 2021) by dividing observed values by expected values, and expressed as ratios. RESULTS: A total of 1,442,737 outpatient visits were recorded. Malaria was suspected in 55.3% of visits and 98.8% of these had a malaria diagnostic test performed. ITSA showed no differences between observed and expected total outpatient visits, malaria cases, non-malarial visits, or proportion of visits with suspected malaria after COVID-19 onset. However, in the second six months of the COVID-19 time period, there was a smaller mean proportion of patients tested with RDTs compared to expected (relative prevalence ratio (RPR) = 0.87, CI (0.78-0.97)) and a smaller mean proportion of malaria cases prescribed AL (RPR = 0.94, CI (0.90-0.99)). CONCLUSIONS: In the first year after the COVID-19 pandemic arrived in Uganda, there were no major effects on malaria disease burden and indicators of case management at these 17 rural health facilities, except for a modest decrease in the proportion of RDTs used for malaria diagnosis and the mean proportion of malaria cases prescribed AL in the second half of the COVID-19 pandemic year. Continued surveillance will be essential to monitor for changes in trends in malaria indicators so that Uganda can quickly and flexibly respond to challenges imposed by COVID-19.


Subject(s)
Ambulatory Care , COVID-19/epidemiology , Malaria/epidemiology , Chronic Disease Indicators , Humans , Infection Control , Interrupted Time Series Analysis , Malaria/diagnosis , Malaria/therapy , Malaria/transmission , Rural Health , Uganda/epidemiology
3.
Malar J ; 20(1): 481, 2021 Dec 20.
Article in English | MEDLINE | ID: covidwho-1623634

ABSTRACT

BACKGROUND: Malaria causes more than 200 million cases of illness and 400,000 deaths each year across 90 countries. The World Health Organization (WHO) set a goal for 35 countries to eliminate malaria by 2030, with an intermediate milestone of 10 countries by 2020. In 2017, the WHO established the Elimination-2020 (E-2020) initiative to help countries achieve their malaria elimination goals and included 21 countries with the potential to eliminate malaria by 2020. METHODS: Across its three levels of activity (country, region and global), the WHO developed normative and implementation guidance on strategies and activities to eliminate malaria; provided technical support and subnational operational assistance; convened national malaria programme managers at three global meetings to share innovations and best practices; advised countries on strengthening their strategy to prevent re-establishment and preparing for WHO malaria certification; and contributed to maintaining momentum towards elimination through periodic evaluations, monitoring and oversight of progress in the E-2020 countries. Changes in the number of indigenous cases in E-2020 countries between 2016 and 2020 are reported, along with the number of countries that eliminated malaria and received WHO certification. RESULTS: The median number of indigenous cases in the E-2020 countries declined from 165.5 (interquartile range [IQR] 14.25-563.75) in 2016 to 78 (IQR 0-356) in 2020; 12 (57%) countries reported reductions in indigenous cases over that period, of which 7 (33%) interrupted malaria transmission and maintained a malaria-free status through 2020 and 4 (19%) were certified malaria-free by the WHO. Two countries experienced outbreaks of malaria in 2020 and 2021 attributed, in part, to the COVID-19 pandemic. CONCLUSIONS: Although the E-2020 countries contributed to the achievement of the 2020 global elimination milestone, the initiative highlights the difficulties countries face to interrupt malaria transmission, even when numbers of cases are very low. The 2025 global elimination milestone is now approaching, and the lessons learned, experience gained, and updated guidance developed during the E-2020 initiative will help serve the countries seeking to eliminate malaria by 2025.


Subject(s)
Disease Eradication , Global Health , Malaria/epidemiology , Malaria/prevention & control , World Health Organization , Endemic Diseases/prevention & control , Guidelines as Topic , Humans , Malaria/transmission , Population Surveillance
4.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(1): 7-9, 2020 Feb 27.
Article in Chinese | MEDLINE | ID: covidwho-1456574

ABSTRACT

Since the end of 2019, the coronavirus disease 2019 (COVID-19) has been extensively epidemic in China, which not only seriously threatens the safety and health of Chinese people, but also challenges the management of other infectious diseases. Currently, there are still approximately three thousand malaria cases imported into China every year. If the diagnosis and treatment of malaria cases as well as the investigation and response of the epidemic foci are not carried out timely, it may endanger patients'lives and cause the possible of secondary transmission, which threatens the achievements of malaria elimination in China. Due to the extensive spread and high transmission ability of the COVID-19, there is a possibility of virus infections among malaria cases during the medical care-seeking behaviors and among healthcare professionals during clinical diagnosis and treatment, sample collection and testing and epidemiological surveys. This paper analyzes the challenges of the COVID-19 for Chinese malaria elimination programme, and proposes the countermeasures in response to the COVID-19 outbreak, so as to provide the reference for healthcare professionals.


Subject(s)
Coronavirus Infections/epidemiology , Disease Outbreaks , Malaria , Pneumonia, Viral/epidemiology , Betacoronavirus , COVID-19 , China , Coronavirus Infections/prevention & control , Humans , Malaria/epidemiology , Malaria/prevention & control , Malaria/transmission , National Health Programs , Pneumonia, Viral/prevention & control , SARS-CoV-2
5.
Emerg Med Clin North Am ; 39(3): 453-465, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1263258

ABSTRACT

The role of the emergency provider lies at the forefront of recognition and treatment of novel and re-emerging infectious diseases in children. Familiarity with disease presentations that might be considered rare, such as vaccine-preventable and non-endemic illnesses, is essential in identifying and controlling outbreaks. As we have seen thus far in the novel coronavirus pandemic, susceptibility, severity, transmission, and disease presentation can all have unique patterns in children. Emergency providers also have the potential to play a public health role by using lessons learned from the phenomena of vaccine hesitancy and refusal.


Subject(s)
Communicable Diseases, Emerging/epidemiology , Pediatrics , COVID-19/diagnosis , COVID-19/therapy , COVID-19/transmission , Chickenpox/diagnosis , Chickenpox/therapy , Chickenpox/transmission , Chikungunya Fever/diagnosis , Chikungunya Fever/therapy , Chikungunya Fever/transmission , Child , Communicable Diseases, Emerging/immunology , Decision Trees , Dengue/diagnosis , Dengue/therapy , Dengue/transmission , Emergency Medicine , Hemorrhagic Fever, Ebola/diagnosis , Hemorrhagic Fever, Ebola/therapy , Hemorrhagic Fever, Ebola/transmission , Humans , Incidence , Malaria/diagnosis , Malaria/therapy , Malaria/transmission , Measles/diagnosis , Measles/therapy , Measles/transmission , Physician's Role , Public Health , SARS-CoV-2 , Systemic Inflammatory Response Syndrome , Travel-Related Illness , Vaccination , Vaccination Refusal , Whooping Cough/diagnosis , Whooping Cough/therapy , Whooping Cough/transmission , Zika Virus Infection/diagnosis , Zika Virus Infection/therapy , Zika Virus Infection/transmission
6.
Infect Dis Poverty ; 10(1): 5, 2021 Jan 07.
Article in English | MEDLINE | ID: covidwho-1015905

ABSTRACT

BACKGROUND: The pandemic of the coronavirus disease 2019 (COVID-19) has caused substantial disruptions to health services in the low and middle-income countries with a high burden of other diseases, such as malaria in sub-Saharan Africa. The aim of this study is to assess the impact of COVID-19 pandemic on malaria transmission potential in malaria-endemic countries in Africa. METHODS: We present a data-driven method to quantify the extent to which the COVID-19 pandemic, as well as various non-pharmaceutical interventions (NPIs), could lead to the change of malaria transmission potential in 2020. First, we adopt a particle Markov Chain Monte Carlo method to estimate epidemiological parameters in each country by fitting the time series of the cumulative number of reported COVID-19 cases. Then, we simulate the epidemic dynamics of COVID-19 under two groups of NPIs: (1) contact restriction and social distancing, and (2) early identification and isolation of cases. Based on the simulated epidemic curves, we quantify the impact of COVID-19 epidemic and NPIs on the distribution of insecticide-treated nets (ITNs). Finally, by treating the total number of ITNs available in each country in 2020, we evaluate the negative effects of COVID-19 pandemic on malaria transmission potential based on the notion of vectorial capacity. RESULTS: We conduct case studies in four malaria-endemic countries, Ethiopia, Nigeria, Tanzania, and Zambia, in Africa. The epidemiological parameters (i.e., the basic reproduction number [Formula: see text] and the duration of infection [Formula: see text]) of COVID-19 in each country are estimated as follows: Ethiopia ([Formula: see text], [Formula: see text]), Nigeria ([Formula: see text], [Formula: see text]), Tanzania ([Formula: see text], [Formula: see text]), and Zambia ([Formula: see text], [Formula: see text]). Based on the estimated epidemiological parameters, the epidemic curves simulated under various NPIs indicated that the earlier the interventions are implemented, the better the epidemic is controlled. Moreover, the effect of combined NPIs is better than contact restriction and social distancing only. By treating the total number of ITNs available in each country in 2020 as a baseline, our results show that even with stringent NPIs, malaria transmission potential will remain higher than expected in the second half of 2020. CONCLUSIONS: By quantifying the impact of various NPI response to the COVID-19 pandemic on malaria transmission potential, this study provides a way to jointly address the syndemic between COVID-19 and malaria in malaria-endemic countries in Africa. The results suggest that the early intervention of COVID-19 can effectively reduce the scale of the epidemic and mitigate its impact on malaria transmission potential.


Subject(s)
COVID-19/epidemiology , COVID-19/therapy , Malaria/epidemiology , Malaria/therapy , COVID-19/transmission , COVID-19/virology , Ethiopia/epidemiology , Humans , Malaria/transmission , Markov Chains , Nigeria/epidemiology , Pandemics , SARS-CoV-2/isolation & purification , Syndemic , Tanzania/epidemiology , Zambia/epidemiology
7.
Global Health ; 16(1): 118, 2020 12 17.
Article in English | MEDLINE | ID: covidwho-979580

ABSTRACT

BACKGROUND: Since 2016 Venezuela has seen a collapse in its economy and public health infrastructure resulting in a humanitarian crisis and massive outward migration. With the emergence of the novel coronavirus SARS-CoV-2 at the end of 2019, the public health emergency within its borders and in neighboring countries has become more severe and as increasing numbers of Venezuelans migrants return home or get stuck along migratory routes, new risks are emerging in the region. RESULTS: Despite clear state obligations to respect, protect and fulfil the rights to health and related economic, social, civil and political rights of its population, in Venezuela, co-occurring malaria and COVID-19 epidemics are propelled by a lack of public investment in health, weak governance, and violations of human rights, especially for certain underserved populations like indigenous groups. COVID-19 has put increased pressure on Venezuelan and regional actors and healthcare systems, as well as international public health agencies, to deal with a domestic and regional public health emergency. CONCLUSIONS: International aid and cooperation for Venezuela to deal with the re-emergence of malaria and the COVID-19 spread, including lifting US-enforced economic sanctions that limit Venezuela's capacity to deal with this crisis, is critical to protecting rights and health in the country and region.


Subject(s)
COVID-19/prevention & control , Emigration and Immigration/statistics & numerical data , Human Rights/standards , Malaria/transmission , COVID-19/epidemiology , Economic Recession/statistics & numerical data , Human Rights/trends , Humans , Malaria/epidemiology , Refugees/statistics & numerical data , Venezuela/epidemiology
8.
PLoS One ; 15(11): e0241680, 2020.
Article in English | MEDLINE | ID: covidwho-949091

ABSTRACT

Malaria remains one of the most prevalent infectious diseases in the tropics and subtropics, and Mozambique is not an exception. To design geographically targeted and effective intervention mechanisms of malaria, an up-to-date map that shows the spatial distribution of malaria is needed. This study analyzed 2018 Mozambique Malaria Indicator Survey using geostatistical methods to: i) explore individual, household, and community-level determinants of malaria in under-five children, ii) prepare a malaria prevalence map in Mozambique, and iii) produce prediction prevalence maps and exceedence probability across the country. The results show the overall weighted prevalence of malaria was 38.9% (N = 4347, with 95% CI: 36.9%-40.8%). Across different provinces of Mozambique, the prevalence of malaria ranges from 1% in Maputo city to 57.3% in Cabo Delgado province. Malaria prevalence was found to be higher in rural areas, increased with child's age, and decreased with household wealth index and mother's level of education. Given the high prevalence of childhood malaria observed in Mozambique there is an urgent need for effective public health interventions in malaria hot spot areas. The household determinants of malaria infection that are identified in this study as well as the maps of parasitaemia risk could be used by malaria control program implementers to define priority intervention areas.


Subject(s)
Malaria/epidemiology , Animals , Child, Preschool , Culicidae , Female , Humans , Infant , Malaria/transmission , Models, Theoretical , Mozambique , Prevalence , Risk Factors , Socioeconomic Factors
10.
Bull Math Biol ; 82(4): 47, 2020 04 02.
Article in English | MEDLINE | ID: covidwho-30620

ABSTRACT

People infected with malaria may receive less mosquito bites when they are treated in well-equipped hospitals or follow doctors' advice for reducing exposure to mosquitoes at home. This quarantine-like intervention measure is especially feasible in countries and areas approaching malaria elimination. Motivated by mathematical models with quarantine for directly transmitted diseases, we develop a mosquito-borne disease model where imperfect quarantine is considered to mitigate the disease transmission from infected humans to susceptible mosquitoes. The basic reproduction number [Formula: see text] is computed and the model equilibria and their stabilities are analyzed when the incidence rate is standard or bilinear. In particular, the model system may undergo a subcritical (backward) bifurcation at [Formula: see text] when standard incidence is adopted, whereas the disease-free equilibrium is globally asymptotically stable as [Formula: see text] and the unique endemic equilibrium is locally asymptotically stable as [Formula: see text] when the infection incidence is bilinear. Numerical simulations suggest that the quarantine strategy can play an important role in decreasing malaria transmission. The success of quarantine mainly relies on the reduction of bites on quarantined individuals.


Subject(s)
Malaria/transmission , Models, Biological , Quarantine , Animals , Anopheles/parasitology , Basic Reproduction Number/statistics & numerical data , Computer Simulation , Host-Parasite Interactions , Humans , Incidence , Malaria/epidemiology , Malaria/prevention & control , Mathematical Concepts , Mosquito Vectors/parasitology , Quarantine/statistics & numerical data
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