Laboratory surveillance of invasive Haemophilus influenzae disease in Argentina, 2011-2019

Abstract The incorporation of Haemophilus influenzae type b (Hib) vaccine into the Argentine National Immunization Program in 1998 resulted in a dramatic decrease in the incidence of invasive disease due to this serotype. We assessed 1405 H. influenzae (Hi) isolates causing invasive infections referred to the National Reference Laboratory between 2011 and 2019. Non-encapsulated Hi were the most common strains (44.5%), followed by types b (41.1%) and a (10.0%). Significant increase in the proportion of type b was observed, from 31.2% in 2011, to 50% in 2015, correlating with the peak incidence rate, later decreasing to 33.6% by 2019. We compared the genetic relationship between clones circulating during the period of increased Hib incidence (2011-2015) and those of the prevaccination-transition period (1997-1998). Four pulsotypes predominated in both periods, G, M, P and K, G being the most common. Multilocus sequence typing revealed that the 4 pulsotypes belonged to ST6, or one of its simple or double locus variants. Isolates from fully vaccinated individuals did not differ from those of the rest of the population studied. After ruling out aspects associated with emergence of specific clones, we concluded that factors such as low booster coverage rates, delayed vaccination schedules and use of different vaccines may have contributed to the reemergence of Hib infections.

Resumen La introducción de la vacuna contra Haemophilus influenzae tipo b (Hib) en el Programa Nacional de Inmunización de Argentina en 1998 produjo una drástica disminución de la incidencia de enfermedad invasiva causada por este serotipo. En el Laboratorio Nacional de Referencia se estudiaron 1405 aislamientos de H. influenzae causantes de enfermedad invasiva recibidos en el período 2011-2019. H. influenzae no capsulado fue el más frecuente (44,5%), seguido por los tipos b (41,1%) y a (10,0%). Se observó un aumento significativo de la proporción del tipo b, de 31,2% en 2011 a 50% en 2015, que se correlacionó con un pico de incidencia en ese mismo año. Hacia 2019, descendió a 33,6%. Con el objetivo de evaluar los clones circulantes durante el incremento de la proporción de Hib y comparar con el período prevacunal-transición, se determinó la relación genética de una selección de aislamientos de los períodos 1997-1998 y 2011-2015. El análisis por PFGE mostró 4 pulsotipos predominantes en los 2 períodos, G, M, P y K, y el pulsotipo G fue mayoritario en ambos períodos. Por MLST se demostró que los 4 pulsotipos pertenecieron al ST6 o sus variantes (simple o doble locus). Entre los aislamientos de pacientes con vacunación completa no se hallaron clones diferentes respecto del resto de la población. Se postula que las coberturas de vacunación no satisfactorias en las dosis de refuerzo, los esquemas atrasados y el uso de diferentes vacunas pudieron haber contribuido a la reemergencia de Hib.

Re-emergence of human monkeypox 2022: its ecology and public health significance-short review article

Monkeypox virus (MPXV) is one of Orthopoxvirus subfamily, it’s refers to a zoonotic disease caused by MPXV. Human monkeypox, on the other hand, has a much lower morbidity and fatality rate than smallpox. Reference to the current resurgence, monkeypox outbreaks have been reported over the past 5 decades, 10 countries in Africa was initially discovered to be affected by the outbreak and subsequently 4 countries apart from Africa. Additionally, re-emergence of monkeypox in African countries, especially Nigeria about forty 40 years of the initial outbreak, midst 2010-2019. Climate change, deforestation, lack of proper health and research advance infrastructure among the society and uncontrol intake of bush meat in the African countries could have been the reason for the recent re-emergence of monkeypox within the communities. Public health significance of monkeypox outbreak could be the factors related to the vulnerability of the population towards MPXV when smallpox vaccination was stopped. Due to the rapid global outreach of monkeypox endemic, it should be therefore considered as a very serious re-surging pathogen in the world. However, detail and proper observational research could bring more light on the influence of MPXV on overall human population, together with the advancement in qualitative and quantitative of outbreak data collection, research in the current situation is crucial and need an emergency treat in order to encourage the researchers to improve more findings on the monkeypox outbreak, which will subsequently enhances appropriate case management and public health response.

Distribution characteristics of emerging and reemerging Oncomelania hupensis in China from 2015 to 2021 / 中国血吸虫病防治杂志

OBJECTIVE@#To analyze the distribution characteristics of emerging and reemerging Oncomelania hupensis snails after the criteria for transmission control of schistosomiasis were achieved in China, so as to provide insights into assessment of schistosomiasis transmission risk and formulation of snail control strategies during the elimination phase.@*METHODS@#O. hupensis survey data in China from 2015 to 2021 were collected from the National Schistosomiasis Pevention and Control Information Management System, and the distribution characteristics of emerging and reemerging O. hupensis snails were descriptively analyzed.@*RESULTS@#Emerging and reemerging O. hupensis snails were identified in China each year from 2015 to 2021, with relatively larger areas with emerging and reemerging O. hupensis snail habitats in 2016 and 2021, and relatively higher numbers of counties (districts) where emerging and reemerging O. hupensis snails were detected in 2016 and 2021. A total of 4 586.30 hm2 of emerging O. hupensis snail habitats were found in 10 schistosomiasis-endemic provinces of China (except Fujian and Yunnan Provinces) from 2015 to 2021, with 96.80% in Anhui, Hunan and Hubei provinces, where marshland and lake endemic foci were predominant. A total of 21 023.90 hm2 of reemerging O. hupensis snail habitats were found in 12 schistosomiasis-endemic provinces of China from 2015 to 2021, with 97.67% in six provinces of Hubei, Sichuan, Jiangxi, Jiangsu, Yunnan and Anhui, where marshland and lake and hilly endemic regions were predominant. Emerging snail habitats were found in 15.08% of all schistosomiasisendemic counties (districts) in China from 2015 to 2021, and 78.75% of all emerging snail habitats were identified in 11 schistosomiasis-endemic counties (districts), with the largest area of emerging snail habitats found in Lixian County, Hunan Province (645.00 hm2). Reemerging snail habitats were found in 47.67% of all schistosomiasis-endemic counties (districts) in China from 2015 to 2021, and 43.29% of all reemerging snail habitats were identified in 11 schistosomiasis-endemic counties (districts), with the largest area of reemerging snail habitats found in Weishan Li and Hui Autonomous County of Hunan Province (1 579.70 hm2).@*CONCLUSIONS@#Emerging and reemerging O. hupensis snails were identified in China each year from 2015 to 2021, with much larger areas of reemerging snail habitats than emerging snail habitats, and larger numbers of schistosomiasis-endemic provinces and counties (districts) with reemerging snails were found that those of provinces and counties (districts) with emerging snails. Specific snail control interventions are required tailored to the causes of emerging and reemerging snail habitats. Both emergence and reemergence of O. hupensis snails should be paid attention to in marshland and lake endemic areas, and Guangxi Zhuang Autonomous Region, Shanghai Municipality and Zhejiang Province where schistosomiasis had been eliminated, and reemergence of O. hupensis snails should be given a high priority in hilly areas. In addition, monitoring of O. hupensis snails should be reinforced in snail-free areas after flooding.

Malaria and artemisinin resistance: a bibliometric analysis

With roughly 50 % of the global population at risk for infection, malaria is one of the most serious public health problems in the world. This infection is caused by single-celled protozoa of the genus Plasmodium. By the turn of the century, the majority of antimalarial drugs were no longer effective against Plasmodium falciparum. However, one year after World Health Organization's final endorsement for the global use of ACTs, an appearance of artemisinin-resistant Plasmodium falciparum was seen in the border regions of Thailand and Cambodia and has since spread to other areas on the globe in subsequent years. The purpose of this work is to summarize the knowledge structure and trend of malaria and artemisinin resistance from 2012 to 2022. The VOS viewer application was used to bibliometrically analyze publications from 2012 to 2022. A total of 169 papers that discussed the keywords were used. VOS viewer application was used to produce maps based on the scientific data between the top authors and top terms in clusters. The research trend of artemisinin resistance and malaria was reported to be on the decline from 2019 to 2022. The bibliographic analysis offered an intellectual framework for the study area by identification of research groups and themes. The years with the most publications were 2015-2017, with 23 articles published each year. The most often used keywords in the research were artemisinin resistance (38 occurrences). The spread of artemisinin-resistant P. falciparum in significant regions of Southeast Asia threatens to destabilize malaria control globally. One of the most pressing global health concerns today is preventing artemisinin resistance from spreading to Africa, where the consequences for childhood mortality might be severe.

Evaluation des risques de réémergence de l'épidémie du virus Chikungunya dans la vallée du Monastère de Mont Ngafula, RD Congo

Contexte et objectif. L'épidémie à virus Chikungunya est émergente, invalidante et mortelle qui sévi partout. Le virus Chikungunya est transmis à l'homme par la piqûre des insectes infectés du genre Aedes. A Kinshasa, le récent épisode de l'épidémie remonte à 4 années. L'objectif de la présente étude a été d'évaluer les risques de réémergence de l'épidémie du virus Chikungunya à Kinshasa Mont Ngafula. Méthodes. Il s'agissait d'une étude transversale menée à Mont Ngafula, dans laquelle 4 sites ont été sélectionnés à l'aide d'un plan d'échantillonnage à plusieurs degrés du 1er juin au 30 août 2021. Les larves et les nymphes des insectes ont constitué le matériel biologique de l'étude. Des variables environnementales (Température, pH, turbidité, Conductivité et Saturation en oxygène) ont été recueillies dans les gîtes larvaires. Une analyse de régression logistique multivariée a été effectuée pour identifier les prédicteurs de la densité des gîtes larvaires. Résultats. 400 ménages et 738 gîtes larvaires ont été explorés. Les indices entomologiques, indice récipient (IR), indice maison (IM) et indice de Breteau (IB) évalués étaient supérieurs aux critères et normes de l'OMS. La saturation en oxygène, la turbidité et la conductivité se sont avérées significativement associées à la densité des gîtes larvaires. Conclusion. Les risques de réémergence de l'épidémie de Chikungunya à Kinshasa sont réels. Une surveillance entomologique est nécessaire pour mettre en place des mesures de prévention et de contrôle de santé publique.

Analysis of re-emergence of Oncomelania snail in Sichuan Province from 2015 to 2019 / 上海预防医学

Objective To analyze the risk of re-emergence of Oncomelania snail(O.snail) from 2015 to 2019, in order to improve the effectiveness of snail control. Methods Collection of report forms and schistosomiasis surveillance data was carried out from 2015 to 2019, and analyzed retrospectively. Results The area of snail-emergence was 6 241.98 hm2 during 2015-2019, 44.29、4 610.18、813.92、446.09 and 327.50 hm2 respectively, for each corresponding year.Among the re-emergence areas, flat-ground subtype was 1 185.49 hm2(18.99%), hilly subtype was 2 536.58 hm2(40.64%), and mountain subtype was 2 519.91 hm2(40.37%).The top 5 cities with O.snail re-emergence areas were Liangshanzhou(2016), Ya′an(2016), Deyang(2016), Meishan(2016), and Meishan(2017).The top 5 disticts with O.snail re-emergence areas were Renshou, Puge, Lushan, Tianquan and Dechang. Conclusion The re-emergence of O.snail attributes to several factors, such as low quality of annual snail survey, unitary method of elimination and complexity of snail habit environment.Surveillance and supervision on the sources of infection and snail spreading should continue with exploration of new method in eliminating snails especially in hilly regions.

Pertussis, historia, hechos y situación actual / Pertussis, history, facts, and current situation / Pertussis, história, fatos e situação atual

Pertussis, tos convulsa o coqueluche son términos que se emplean como sinónimos para referirse a una infección respiratoria inmunoprevenible grave causada por la bacteria gram negativa denominada Bordetella pertussis. La mejor manera de prevenir la enfermedad es a través de la vacunación. Las primeras experimentaciones con vacunas comenzaron después de que Jules Bordet y Octave Gengou del Instituto Pasteur de Bruselas identificaran el agente etiológico en 1906. Estas primeras vacunas se hicieron a partir de células enteras del agente causal muertas por calor. La historia de las vacunas contra la enfermedad continuó desde aquel entonces con vacunas combinadas y luego con vacunas de componentes o acelulares. Su uso masivo desde los años 50 permitió una reducción muy marcada de la morbimortalidad asociada a la enfermedad. Sin embargo en el año 2008, se estimó que en el mundo se producen por año 16 millones de casos de los cuales 195.000 resultan ser fatales. Para el año 2014 esta estimación sobre el número de casos creció a 24,1 millones de casos en el año. El incremento del número de casos detectado en los últimos 20 años ha estado dirigiendo la mirada de la comunidad sanitaria y científica hacia la identificación de causas de esta nueva situación epidemiológica de pertussis para revisar e implementar estrategias de control más efectivas. Se ha logrado así un mejor reconocimiento de la enfermedad no solo entre los lactantes y los niños, sino también en los adolescentes y adultos. El mayor reconocimiento de que los niños mayores, los adolescentes y los adultos están en riesgo de contraer la enfermedad y que pueden transmitirla a los más vulnerables ha resaltado la necesidad de comprender mejor la inmunidad inducida por las vacunas y su duración. El rol de las vacunas y en particular de las vacunas acelulares constituidas por pocos inmunógenos en altas dosis sobre la selección de geno/fenotipos bacterianos más resistentes a la inmunidad inducida por las vacunas ha comenzado a visualizarse más claramente. La investigación en curso que utiliza herramientas novedosas sin dudas ha mejorado el conocimiento en general sobre esta patología, sin embargo la investigación debe continuar de forma de lograr una vigilancia más oportuna con terapias y vacunas de nueva generación más eficaces.

Pertussis or whooping cough is a preventable respiratory infectious disease caused by the gram-negative microorganism known as Bordetella pertussis. The best strategy to prevent pertussis is to get vaccinated. Vaccine development began just after Jules Bordet and Octave Gengou at Pasteur Institute from Brussels identified the etiologic agent of the disease in 1906. The first vaccine was formulated with heat-killed B. pertussis bacteria, which was later combined with tetanus and diphtheria toxoids (DTP). The second generation of pertussis vaccine was the acellular vaccine consisting in a few purified B. pertussis immunogens. The massive use of these vaccines since the 50s reduced the morbidity and mortality associated with the disease. However, in 2008 it was estimated that 16 million cases occurred by year with 195,000 deaths worldwide. For 2014, this estimation rised to 24.1 million cases per year. The increase in the number of cases detected in the last 20 years has been directing the attention of the health and scientific community towards the identification of causes of this new epidemiological situation of pertussis to review and implement more effective control strategies. This has achieved a better recognition of the disease not only among infants and children but also in adolescents and adults. The awareness that older children, adolescents and adults are at risk of contracting the disease and that they can transmit pertussis to the most vulnerable highlighted the need to better understand the immunity induced by pertussis vaccination and also the duration of such immunity. Another aspect that needs to be understood is that related to the selection pressure that the vaccines would be exerting (in particular the acellular vaccines) on the circulating bacterial population. In this sense, an increase in the prevalence of strains of B. pertussis that are more resistant to the immunity conferred by the vaccines has been detected. The ongoing research using innovative tools has undoubtedly improved the knowledge on pertussis; however research should continue to achieve a more timely surveillance with more effective new generation therapies and vaccines.

Pertussis, tosse convulsa ou coqueluche são termos que se utilizam como sinônimos para fazer referência a uma infecção respiratória imunoprevenível grave provocada pela bactéria gram negativa denominada Bordetella pertussis. A melhor forma de prevenir a doença é através da vacinação. As primeiras experimentações com vacinas começaram depois de que Jules Bordet e Octave Gengou do Instituto Pasteur de Bruxelas identificassem o agente etiológico em 1906. Estas primeiras vacinas foram feitas a partir de células inteiras do agente causal mortas por calor. A história das vacinas contra a doença continuou a partir de então com vacinas combinadas e depois com vacinas de componentes ou acelulares. O uso generalizado delas desde os anos 50 permitiu uma redução muito importante da morbimortalidade associada à doença. Entretanto, no ano 2008, a estimativa foi de 16 milhões de casos produzidos no mundo por ano dos quais 195.000 resultaram fatais. Para o ano 2014, essa estimativa sobre o número de casos cresceu a 24,1 milhões de casos no ano. O aumento do número de casos detectado nos últimos 20 anos dirigiu e dirige o foco da comunidade sanitária e científica para a identificação de causas dessa nova situação epidemiológica de coqueluche de forma de revisar e implementar estratégias de controle mais efetivas. Um melhor reconhecimento da doença foi assim possível, não só entre bebês e meninos, mas também nos adolescentes e adultos. O maior reconhecimento de que as crianças mais velhas, os adolescentes e os adultos estão em risco de contrair a doença e que pode transmiti-la aos mais vulneráveis tem salientado a necessidade de compreender melhor a imunidade induzida pelas vacinas e a duração delas. O papel das vacinas e, em particular, das vacinas acelulares constituídas por poucos imunógenos em altas doses sobre a seleção de genótipos/fenótipos bacterianos mais resistentes à imunidade induzida pelas vacinas tem começado a ser visualizado mais claramente. A pesquisa em andamento que utiliza ferramentas novas, sem dúvidas, tem melhorado o conhecimento em geral sobre essa patologia, contudo a pesquisa deve continuar de maneira de alcançar uma vigilância mais oportuna com terapias e vacinas de nova geração mais eficazes.

Reemergence of Foot and Mouth Disease in Andaman and Nicobar Islands, India

Foot-and-mouth disease (FMD) is an acute highly contagious viral disease of cloven-hoofed animals which has been discovered more than 100 years ago. The causative organism is a RNA virus belongs to the Aphthovirus genus, Picornaviridae family. The disease is endemic in India and every year the economic loss due to direct and indirect cause is more than USD 4 billion annually. The Andaman & Nicobar Islands also suffered due to the outbreak of FMD in the year 2005 which was due to serotype O. However, in the present study the reemergence of FMD virus almost after a gap of 13 years has been reported from the South Andaman district of the A & N Islands. The outbreak was confirmed as serotype O and is mainly affected more than 800 cattle, goat and buffalo population. The reemergence of the FMD virus in the islands has posed a serious concern to the livestock of this island which is now being considered as almost free from many of the dreaded disease. Based on the epidemiological investigation it could be concluded that the virus might have entered through the transport of straws which is being used as packing materials for vegetable and fruits from mainland

Reemergencia de la rabia animal a partir de 2007 en el municipio de Santiago de Cuba / Reemergence of the animal rage since 2007 in Santiago de Cuba municip

Se efectuó un estudio descriptivo y transversal para caracterizar algunas variables clinicoepidemiológicas de la rabia animal notificadas durante 2007, 2010, 2012 y 2015. Las estadísticas de esta zoonosis se obtuvieron en la Unidad Municipal de Higiene y Epidemiología del municipio de Santiago de Cuba. El universo de positividad estuvo constituido por 31 animales, con un predominio de perros (93,5 por ciento) y mangostas (6,4 por ciento). En el 2007 se notificó la mayor cantidad de canes (15) y el área de salud más afectada fue la del Policlínico Frank País García, con sus consejos populares Agüero-Mar verde y Manuel Isla. Prevalecieron los perros satos (55,2 por ciento) y la tasa de rabia fue de 6,4 por cada 100 000 canes, los cuales lesionaron a 73 personas (34 por año). Estos datos muestran el riesgo de adquirir rabia humana, por lo cual se debe prevenir la rabia animal

A descriptive and cross-sectional study was carried out, to characterize some clinical and epidemiological variables of the animal rage notified during 2007, 2010, 2012 and 2015. The statistics of these zoonosis were obtained in the Municipal Unit of Hygiene and Epidemiology from Santiago de Cuba municipality. The positivity universe was constituted by 31 animals, with a prevalence of dogs (93,5 percent) and mongeese (6,4 percent). In 2007 the highest quantity in dogs was notified (15), and the most affected health area was that of Frank País García Polyclinic, with its popular councils Agüero-Mar Verde and Manuel Isla. Dogs without race prevailed (55,2 percent) and the rage rate was 6,4 every 100 000 dogs, which injured 73 people, (34 per year). These data show the risk of acquiring human rage, reason why the animal rage should be prevented

Reemergence of porcine epidemic diarrhea virus on Jeju Island / 대한수의학회지

Porcine epidemic diarrhea virus (PEDV) strains responsible for recent outbreaks in the United States have been occurring in Mainland Korea since late 2013. Over the past 10 years, PEDV outbreaks have not been reported on Jeju Island. However, in late March of 2014, PEDV re-emerged on Jeju Island and was found to be genetically identical to PEDV strains currently circulating in Mainland Korea. The present study was conducted to provide a better understanding of the epidemiology of PEDV and more effective preventive measures against PED.

Reemergence of porcine epidemic diarrhea virus on Jeju Island / 대한수의학회지

Porcine epidemic diarrhea virus (PEDV) strains responsible for recent outbreaks in the United States have been occurring in Mainland Korea since late 2013. Over the past 10 years, PEDV outbreaks have not been reported on Jeju Island. However, in late March of 2014, PEDV re-emerged on Jeju Island and was found to be genetically identical to PEDV strains currently circulating in Mainland Korea. The present study was conducted to provide a better understanding of the epidemiology of PEDV and more effective preventive measures against PED.

Status of Plasmodium vivax Malaria in the Republic of Korea after Reemergence / 한양의대학술지

The annual number of Plasmodium vivax malaria cases had rapidly increased since its reemergence in the Republic of Korea (ROK) in 1993 to reach more than 4,000 cases in 2000. Since 2001, it began to decrease to 864 cases in 2004, and once again increased to reach more than 2,000 cases by 2007. P. vivax malaria mainly has occurred in the areas adjacent to the Demilitarized Zone, which implies that current malaria occurrence in ROK has been strongly influenced by malaria situation of the Democratic People's Republic of Korea (DPRK). Besides the direct influence from DPRK, local transmission within ROK also likely occurred. Chemoprophylaxis performed in the ROK Army since 1997 has contributed to the reduction in cases among military personnel. However, many prophylactic failure cases due to the resistance to the prophylactic regimen have been reported since 2000 and two cases of chloroquine (CQ)-resistant P. vivax were reported, representing the first-known cases of CQ-resistant P. vivax from a temperate region of Asia. Delayed recrudescence, a kind of level I-resistance against CQ, has occurred frequently in DPRK. Continuous surveillance and monitoring are warranted to prevent further expansion of CQ-resistant P. vivax in ROK and DPRK.

Enfermedades reemergentes: factores causales y vigilancia: [review] / Reemergent diseases: causal factors and surveillance: [revisión]

La emergencia y reemergencia de las enfermedades infecciosas posee muchos factores interrelacionados. La interconectividad global continúa en aumento a través del comercio, las relaciones culturales, económicas, políticas y las relaciones hombre- hombre y animal-hombre. Estas interrelaciones incluyen las accidentales y las programadas, donde se intercambian agentes microbianos además de su resistencia, lo que da pie a la emergencia de enfermedades emergentes y reemergentes. La solución a la expansión de estas entidades requiere un esfuerzo cooperativo de varias disciplinas mundiales. Se realizó una revisión bibliográfica que resume los factores que contribuyen a esta reemergencia.

The emergence and re-emergence of infectious diseases involves many interrelated factors. Global interconnectedness continues to increase with international travel and trade; economic, political, and cultural interactions; and human-to-human and animal-to-human interactions. These interactions include the accidental and deliberate sharing of microbial agents and antimicrobial resistance and allow the emergence of new and unrecognized microbial disease agents. Solutions to limiting the spread of emerging infectious diseases will require cooperative efforts among many disciplines and entities worldwide. This article defines emerging infectious diseases, summarizes historical background, and discusses factors that contribute to emergence.

Risk assessment of re-emerging Plasmodium falciparum on Ishigaki Island using a stochastic transmission model

On Ishigaki Island, <I>Plasmodium falciparum</I> and <I>Plasmodium vivax</I> epidemics occurred in 1945-1946 and were successfully suppressed. The epidemic re-emerged in 1949 because many settlers immigrated to the former endemic areas, but it terminated in 1961. The present study aimed at predicting an outbreak of a new epidemic based on the situation in which <I>P. falciparum</I> malaria patients stay on Ishigaki Island and also examined the re-emergence of the <I>P. falciparum</I> epidemic in 1951-1960 to determine the reliability of the model.<br>A stochastic transmission model of <I>P. falciparum</I> was constructed to detect a small number of infected persons. The seasonal fluctuation of the <I>Anopheles minimus</I> population obtained by observational data and meteorological data through statistical processing was introduced into the model.<br>Simulations were carried out to predict the risk of a new epidemic with scenarios in which the attribute of index patient, visiting season, and reduced inoculation rates of <I>An. minimus</I> were assumed. When an infected person visited the island in summer, a small number of patients with primary infections derived from the index patient appeared for all 1,000-iterations. On the other hand, when an infected person visited the island in winter, few or no patients with primary infections appeared for any of the 1,000-iterations because of the low mosquito density. In realistic conditions, the simulation results showed that there was little possibility of the occurrence of <I>P. falciparum</I> infection.

Plasmodium vivax Malaria: Status in the Republic of Korea Following Reemergence

The annual incidence of Plasmodium vivax malaria that reemerged in the Republic of Korea (ROK) in 1993 increased annually, reaching 4,142 cases in 2000, decreased to 864 cases in 2004, and once again increased to reach more than 2,000 cases by 2007. Early after reemergence, more than two-thirds of the total annual cases were reported among military personnel. However, subsequently, the proportion of civilian cases increased consistently, reaching over 60% in 2006. P. vivax malaria has mainly occurred in the areas adjacent to the Demilitarized Zone, which strongly suggests that malaria situation in ROK has been directly influenced by infected mosquitoes originating from the Democratic People's Republic of Korea (DPRK). Besides the direct influence from DPRK, local transmission within ROK was also likely. P. vivax malaria in ROK exhibited a typical unstable pattern with a unimodal peak from June through September. Chemoprophylaxis with hydroxychloroquine (HCQ) and primaquine, which was expanded from approximately 16,000 soldiers in 1997 to 200,000 soldiers in 2005, contributed to the reduction in number of cases among military personnel. However, the efficacy of the mass chemoprophylaxis has been hampered by poor compliance. Since 2000, many prophylactic failure cases due to resistance to the HCQ prophylactic regimen have been reported and 2 cases of chloroquine (CQ)-resistant P. vivax were reported, representing the first-known cases of CQ-resistant P. vivax from a temperate region of Asia. Continuous surveillance and monitoring are warranted to prevent further expansion of CQ-resistant P. vivax in ROK.

Reemergence of the bedbug Cimex lectularius in Seoul, Korea

A healthy 30-yr-old woman carrying an insect that had been caught in her living room visited the International Clinic at Severance Hospital, Seoul, in December 2007. The insect she brought was identified to be a nymph of a bedbug, Cimex lectularius, and her skin rashes looked typical bedbug's bites. Her apartment was investigated, and a dead body of a bedbug, cast skins, and hatched eggs were found in her rooms and neighbors' rooms in the same building. She was living in that apartment in Seoul for 9 months since she had moved from New Jersey, USA. We assume that the bedbugs were introduced from abroad, since there had been no report on bedbugs in Seoul for more than 2 decades at least. This is a report of a reemergence of the common bedbug, C. lectularius in Seoul, Korea.

Reemergence of Malaria in Korea

Malaria is one of the most important tropical diseases but also occurring in many temperate regions. After more than 10 years' absence, vivax malaria reemerged in Korea in 1993. The annual occurrence has been increased rapidly, reaching 4,142 cases in 2000. It started to decrease and fell to 826 cases in 2004. Recently, however, the incidence tends to increase. Anopheles sinensis is the major vector of malaria in Korea, and its vectorial capacity is low. This endemic occurred in the northern part of South Korea near the Demilitarized Zone (DMZ). The patients suffered from the typical illness of vivax malaria. It is noteworthy that thrombocytopenia occurred in more than 70% of the patients. It is believed that the malaria is properly diagnosed and treated over the nation along the accumulation of experience. To control the disease, more elaborated programs should be conducted in collaboration with North Korea.

Status of Vivax Malaria in the Republic of Korea

Vivax malaria reemerged in the Republic of Korea in 1993. The number of cases of vivax malaria had increased annually until 2000; however, it has decreased constantly since 2001. During the early years after the reemergence, most of the cases occurred among soldiers especially in the region adjacent to the Demilitarized Zone until 1995; however, since 2001, civilian cases have accounted for approximately a half of total cases, also occurring in the neighbor counties of Seoul. Local transmission within the Republic of Korea was already done before the year of 2000. The current status of vivax malaria appears to be in a subsiding phase; however, continuous attentions are needed to prevent further spreading of malaria.

Re-emergence of Schistosomiasis in Dali City after the Criteria of Transmission Control Were Met / 中国寄生虫学与寄生虫病杂志

Objective To analyze the epidemic situation on schistosomiasis in five years after reaching the criteria of transmission control in 1995 in Dali City. . Methods. Epidemiological data of schistosomiasis during 1995-2000 were collected and analyzed. . Results . Stool positive rate in the population was increasing yearly, new cases of infection including cases under 14 years old were detected each year. Acute infection occurred during 1996-1998 consecutively. Stool positive rate in cattle was unstable. Snail-ridden area increased significantly in 1996 and spots with infected snails stayed at a higher level during 1997-2000. . Conclusion . Schistosomiasis in Dali city has been re-emerging though it was once deemed under transmission control. Possible reasons include a low drug-taking rate though distributed, frequent movement of cattle population, and less activity on snail control.