Three anopheline mosquitoes in Korea were studied for their abilities as vectors for Plasmodium vivax. The female mosquitoes of Anopheles lesteri, An. pullus and An. sinensis were allowed to suck malaria patient blood until fully fed, and they were then bred for 2 weeks to develop from malaria parasites to sporozoites. The result from the above confirmed the sporozoites in one An. lesteri of one individual and five An. sinensis of six individuals. We also reconfirmed that An. sinensis was the main vector to transmit malaria and An. lesteri as well as An. sinensis were able to carry Korean malaria parasites. Therefore, we propose that diversified study is needed to manage malaria projects.
Adult ; Animals ; Culicidae/*parasitology/*physiology ; Female ; Humans ; *Insect Vectors ; Korea ; Malaria/parasitology/transmission ; Male ; *Plasmodium vivax

A survey of mosquitoes, including the vector status of Brugia malayi filariasis and their relative larval density, was conducted from 2002 to 2005 at several southern remote islands of Jeollanam-do (province), Gyeongsangnam-do, and Jeju-do, Korea, where filariasis was previously endemic. Overall, a total of 9 species belonging to 7 genera were collected. Ochlerotatus togoi (formerly known as Aedes togoi), Anopheles (Hyrcanus) group, and Culex pipiens were the predominant species captured at all areas. Oc. togoi larvae were most frequently collected at salinity levels <0.5% during June and July, with densities decreasing sharply during the rainy season in August. The most likely explanation for the eradication of filariasis in these areas is suggested to be an aggressive treatment program executed during the 1970s and the 1990s. However, high prevalence of the vector mosquitoes may constitute a potential risk for reemerging of brugian filariasis in these areas.
Animals ; Brugia malayi/parasitology ; Culicidae/*classification/growth & development/parasitology ; Humans ; Insect Vectors/*classification/growth & development/parasitology ; Population Density ; Prevalence ; Republic of Korea ; Seasons

We investigated population densities of mosquitoes infected with sporozoites in three highly epidemic areas of Josan-ri and Jangpa-ri (Paju City) and Dongjung-ri (Yeoncheon County) in Korea. Anopheline mosquitoes were collected from both indoors and outdoors by human baiting collection method during the period of the first week of June to the second week of September 1999. Total 13,296 female mosquitoes were collected and 8,650 (65.1%) were Anophelines. Thirty seven percent (3,199) of the Anopheline mosquitoes were captured outdoors and 63.9% (5,531) indoors. Employing a sandwich enzyme-linked immunosorbent assay (ELISA), we analyzed a total of 7,820 Anopheline mosquitoes and found that 7 Anopheline mosquitoes were infected with sporozoites. The positive rate in Josan-ri was 0.14% (5/3,500) and 0.15% (2/1,370) in Jangpa-ri. The total positive rate in all three surveyed areas was 0.09% (7/7,820). The mosquitoes infected with the sporozoites were detected on June 28th (n=2), July 5th (n=1), July 19th (n=1), August 9th (n=1), September 6th (n=1), and the last one on September 13th (n=1). They were all classified as Anopheles sinensis, which showed positive reaction in ELISA test. Therefore it might be concluded that A. sinensis plays an important role in re-emerging malaria transmission in Korea.
Animals ; Culicidae/*parasitology ; Enzyme-Linked Immunosorbent Assay ; Female ; Human ; Korea/epidemiology ; Malaria, Vivax/epidemiology/parasitology/transmission ; Plasmodium vivax/*isolation & purification ; Support, Non-U.S. Gov't

OBJECTIVETo evaluate the effect of preventive medicine for residents living around mosquito breeding water during rest period of malaria by delimiting a certain range.

METHODThe study adopted the stratified cluster random sampling method to select subjects from 6 counties in the high epidemic area along and north of the Huai River since March 2007. Then the villages of 6 counties were stratified into five levels according to the case reported in year 2006, and one village was randomly selected from each level, thereby 30 villages were selected in total.300-500 subjects were interviewed in each village, and in total 12 860 subjects were recruited in the study. The five selected villages in each county were allocated to three intervention groups according to the block randomization method. The first intervention group included 9 villages, 4362 people; the second intervention group was consisted of 12 villages, 4471 people; the non-intervention group had 9 villages, 4027 people. The basic information of the subjects were collected by questionnaire to analyze the relation between malaria cases and the distribution of the mosquito breeding water, then accordingly delimited the range for preventive medicine. Group 1 received the delimiting preventive medicine treatment, group 2 received routine medicine treatment, while non-treatment group received no treatment. The morbidity, standardized morbidity, net change of morbidity (the D-value of the standardized morbidity before and after the intervention), age-specified incidence, and the protective rate (PR), effectiveness index (IE) and the capture rate of the delimited method group were then calculated.

RESULTSGroup 1 had 1219 (27.9%) people taking medicine and Group 2 had 219 (4.9%) people. In 2006, before the prevention conducting, the high incidence aging group in the first, second and nonintervention group was separately people aging 50 - 59, 60 - 69 and ≥ 70 years old; whose incidence was 36.22‰ (18/497), 40.11‰ (15/374) and 34.88‰ (9/258) respectively. After the intervention, the high incidence aging groups in the first and second intervention group changed to the population over 70 years old, with incidence at 9.17‰ (3/327) and 22.01‰ (7/318) respectively; while the high incidence aging groups in the nonintervention group changed to people aging between 30-39 years old, with the rate at 24.88‰ (10/402). In 2006, the morbidity of malaria in the first, second intervention group and nonintervention group was separately 18.78‰ (83/4420), 20.27‰ (93/4587) and 14.61‰ (53/3627); while the standardized incidence was separately 18.85‰, 20.72‰ and 14.89‰. In 2007, after the prevention conducting, the morbidity in the three groups was 2.75‰ (12/4362), 11.63‰ (52/4471) and 12.17‰ (49/4027), respectively; while the standardized incidences was 2.81‰, 12.75‰ and 12.35‰, respectively. The net value of changes of morbidity in the three groups was separately 16.04%, 7.97% and 2.54%. The difference in net values of changes of morbidity between intervention group 1 and 2 had statistical significance (χ(2) = 7.74, P < 0.05). Comparing with the nonintervention group, the PR and IE in intervention group 1 was separately 84.2% and 6.31; while the capture rate was 69.2% (9/13).

CONCLUSIONThe delimiting preventive medicine treatment during rest period of malaria was very effective for eliminating the potential infection source of malaria and reducing the morbidity of malaria.

Adolescent ; Adult ; Aged ; Animals ; Child ; Child, Preschool ; China ; epidemiology ; Culicidae ; physiology ; Humans ; Incidence ; Infant ; Infant, Newborn ; Malaria ; drug therapy ; epidemiology ; prevention & control ; Middle Aged ; Water ; parasitology ; Young Adult

It is important to understand the dynamics of malaria vectors in implementing malaria control strategies. Six villages were selected from different sections in the Three Gorges Reservoir for exploring the relationship between the climatic factors and its malaria vector density from 1997 to 2007 using the auto-regressive linear model regression method. The result indicated that both temperature and precipitation were better modeled as quadratic rather than linearly related to the density of Anopheles sinensis.
Animals ; China ; Climate ; Culicidae ; physiology ; Insect Vectors ; physiology ; Lakes ; Linear Models ; Malaria ; parasitology ; transmission ; Models, Biological ; Plasmodium ; physiology ; Population Density ; Population Dynamics ; Rain ; Seasons ; Temperature

OBJECTIVETo compare Wuchereria bancrofti (W. bancrofti) infection rates of Culex quinquefasciatus, using dissection and PCR-ELISA in two consecutive time periods (from 2007 to 2008 and from 2008 to 2009).

METHODSMosquitoes were collected in 30 sentinel and 15 non-sentinel sites in 15 Medical Officer of Health areas of Gampaha District known for the presence of W. bancrofti transmission in two consecutive time period of 2007 to 2008 and 2008 to 2009. Captured mosquitoes were dissected to determine the W. bancrofti larvae (L1, L2, L3). PCR was carried out using DNA extracted from mosquito pools (15 body parts/pool) utilizing the primers specific for Wb-SspI repeat. PCR products were analyzed by hybridization ELISA using fluorescein-labeled wild type specific probes. The prevalence of infected/infective mosquitoes in PCR pools (3 pools/site) was estimated using the PoolScreen™ algorithm and a novel probability-based method.

RESULTSOf 45 batches of mosquitoes dissected, W. bancrofti infected mosquitoes were found in 19 and 13 batches, with an infection rate of 13.29% and 3.10% with mean larval density of 8.7 and 1.0 larvae per mosquito for two study periods in the Gampaha District. Total of 405 pools of head, thorax and abdomen were processed by PCR-ELISA for each year. Of these, 51 and 31 pools were positive for W. bancrofti in the two study periods respectively. The association of dissection based prevalence rates with PCR based rates as determined by the Pearson correlation coefficient were 0.176 and 0.890 respectively for the two periods.

CONCLUSIONSData indicate that PCR-ELISA is more sensitive than the traditional dissection techniques for monitoring transmission intensity.

Animals ; Culicidae ; parasitology ; Elephantiasis, Filarial ; epidemiology ; transmission ; Enzyme-Linked Immunosorbent Assay ; Humans ; Polymerase Chain Reaction ; Population Surveillance ; Prevalence ; Sri Lanka ; epidemiology ; Wuchereria bancrofti ; genetics ; immunology

A simple, rapid, and high-throughput method for detection and identification of Wuchereria bancrofti, Brugia malayi, Brugia pahangi, and Dirofilaria immitis in mosquito vectors and blood samples was developed using a real-time PCR combined with high-resolution melting (HRM) analysis. Amplicons of the 4 filarial species were generated from 5S rRNA and spliced leader sequences by the real-time PCR and their melting temperatures were determined by the HRM method. Melting of amplicons from W. bancrofti, B. malayi, D. immitis, and B. pahangi peaked at 81.5+/-0.2degrees C, 79.0+/-0.3degrees C, 76.8+/-0.1degrees C, and 79.9+/-0.1degrees C, respectively. This assay is relatively cheap since it does not require synthesis of hybridization probes. Its sensitivity and specificity were 100%. It is a rapid and technically simple approach, and an important tool for population surveys as well as molecular xenomonitoring of parasites in vectors.
Animals ; Blood/*parasitology ; Brugia/classification/genetics/*isolation & purification ; Cats ; Culicidae/*parasitology ; Dirofilaria immitis/classification/genetics/*isolation & purification ; Dogs ; Humans ; Male ; Parasitology/*methods ; RNA, Helminth/genetics ; RNA, Ribosomal, 5S/genetics ; Real-Time Polymerase Chain Reaction/*methods ; Sensitivity and Specificity ; Transition Temperature ; Wuchereria bancrofti/classification/genetics/*isolation & purification

In Nigeria, malaria causes up to 11% of maternal mortality. Our main aim was to find out the most common mosquito control measures employed by the pregnant women in Lagos and their effects on malaria infection. The study was carried out over a period of 6 months during which trained interviewers administered questionnaires to 400 pregnant women. The prevalence of malaria was 8.4%. There was no significant association between the prevalence of malaria and age, level of education, or occupation of the participants. Pregnant women in the age range 26-30 had the mean parasite density (409.9+/-196.80). Insecticide spray (32.8%), mosquito coil (27.5%), and insecticide-treated nets (ITN) (15.5%) were the major mosquito control measures employed by the participants while the prevalence of infection among them were 2.3%, 6.2%, and 3.2%, respectively (P<0.05). Only 18.3% of the women had taken more than one dose of intermittent preventive treatment (IPT), while another 11.8% had taken a single dose. The infection rate among them was 4.1% and 6.4%, respectively. Malaria prevalence was highest among those who had not received any dose of IPT (10%). This study showed that the use of ITN and IPT among the pregnant women were still unacceptably low. It also showed that the use of insecticide spray which was the most common malaria control measure adopted by the participants was effective despite the fact that it is not a National Malaria Control Policy. We recommend that a sustained integrated mosquito management and public education should be strengthened in Nigeria.
Adolescent ; Adult ; Animals ; *Culicidae/parasitology ; Female ; Health Knowledge, Attitudes, Practice ; Humans ; *Insect Vectors/parasitology ; Insecticides ; Malaria/epidemiology/*prevention & control ; Mosquito Control/*methods ; Nigeria/epidemiology ; Plasmodium/*physiology ; Pregnancy ; Pregnancy Complications, Parasitic/epidemiology/*prevention & control ; Prenatal Care ; Prevalence ; Public Health ; Questionnaires ; Young Adult