Holding back the tiger: Successful control program protects Australia from Aedes albopictus expansion

Soil-transmitted helminth (STH) infections are still a considerable challenge in Myanmar. We undertook a control program for STH infections (especially Trichuris trichiura) among schoolchildren in Myanmar using mass drug administration (MDA) and health education. Around 1,700 schoolchildren from 15 primary schools in 3 suburban districts (Shwe Pyi Thar, Twantay, and Kyauktan) of the Yangon Region were subjected in this study during 2017-2019. All of the schoolchildren in each school were orally administered albendazole (400 mg in a single dose) 2, 3, and 4 times a year in 2017, 2018, and 2019, respectively. The results revealed that the egg positive rate of any intestinal helminths (including STH) was reduced from 37.6% (649/1,724) in 2017 to 22.8% (352/1,542) in 2019. The egg positive rate of Ascaris lumbricoides was decreased remarkably from 23.3% (402/1,724) in 2017 to 3.6% (56/1,542) in 2019. However, that of T. trichiura was only slightly reduced from 26.9% (464/1,724) in 2017 to 20.2% (312/1,542) in 2019. The intensity of infection with A. lumbricoides and T. trichiura was both more or less reduced, and the proportion of light infection cases with A. lumbricoides and T. trichiura increased from 35.6% in 2017 to 64.3% in 2019 and from 70.3% in 2017 to 81.7% in 2019, respectively. The results indicated that repeated MDAs (2-4 times a year for 3 years) using albendazole on schoolchildren in Myanmar failed to control T. trichiura infection. For a successful control of trichuriasis in Myanmar, new MDA strategies, using a modified albendazole regimen (multiple daily doses for 2 or 3 days) or an alternative anthelmintic drug, such as oxantel pamoate, is strongly recommended.

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Biting rhythm, fecundity and longevity rate of Aedes albopictus (Skuse) females from different urbanized settings in Penang Island, Malaysia under uncontrolled laboratory conditions

10.1101/657023 ◽

2019 ◽

Author(s):

Nor Atikah Farhah Muhammad ◽

Nur Faeza Abu Kassim ◽

Abdul Hafiz Ab Majid ◽

Hamady Dieng ◽

Silas Wintuma Avicor

Keyword(s):

Aedes Albopictus ◽

Standard Error ◽

Rural Areas ◽

Disease Transmission ◽

Urban Areas ◽

Environmental Changes ◽

Control Program ◽

Laboratory Strain ◽

Adult Survival ◽

Fecundity Rate

AbstractUrbanization could potentially modify Aedes albopictus’ ecology by changing the dynamics of the species, and increasing the abundance of their breeding sites due to environmental changes, and thus contribute to dengue outbreaks. An efficient control of the vector requires a deeper understanding on the biological components of this vector. Thus, this study was conducted to evaluate the biting rhythm, fecundity and longevity rate of Ae. albopictus in relation to urbanization strata; urban, suburban and rural areas in Penang Island, Malaysia. The experiments were done in comparison to a laboratory strain. Twenty-four hours biting activity of all the mosquito strains showed a clear bimodal biting activity, with morning and evening twilight peaks. A two-way analysis of variance (ANOVA) found that there was statistically no significant interaction (F(69,192) = 1.337, P > 0.05) between the effects of biting time and mosquito strains. Meanwhile, fecundity rates were shown to be statistically significantly different between mosquito strains (F(3,442) = 10.559, P < 0.05) with urban areas having higher mean number of eggs (mean = 107.69, standard error = 3.98) than suburban (mean = 94.48, standard error = 5.18), and rural areas (mean = 72.52, standard error = 3.87). Longevity rates were significantly higher (F(3,441) = 31.259, P < 0.05) for mosquito strains from urban areas compared to the other strains. These findings would provide crucial and relevant fundamental information to the planning of control program in Malaysia, particularly Penang.Author SummaryAedes mosquito populations associated with human habitation in urban area do not only have the potential to cause biting nuisance, but also cause significant public health risks through the transmission of dengue virus. The socioeconomic effects of urbanization have been comprehensively studied by socio-ecologists, but the ecological effects and their impact on this vector biology was not known. The authors found that in Penang Island, the mean number of eggs laid per female of Aedes albopictus is high in the urban areas than those in suburban and rural areas. The survivorship is high for urban populations parallel to the fecundity rate and apparent biting pattern which is peak at dawn and dusk was noted for all Ae. albopictus strains. The changed environment in the urbanized area where more kinds of breeding containers and more blood sources produced by condensed human population supported by warm climate may facilitate larval development, enhance the vector survivorship and its reproductive fitness. These might be the reasons for quick adaptation and susceptibility of Ae. albopictus in urban areas. As higher fecundity rate and longer adult survival may enhance disease transmission, this species studied is indeed need high attention in terms of vector control.

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Successful control program to implement the appropriate antibiotic prophylaxis for cesarean section

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652008000200003 ◽

2008 ◽

Vol 50 (2) ◽

pp. 79-82 ◽

Cited By ~ 2

Author(s):

Silvia Nunes Szente Fonseca ◽

Maria Helena Sofia ◽

Silvana Quintana ◽

Fernanda Dos Santos Nogueira ◽

Anna S. Levin

Keyword(s):

Cesarean Section ◽

Intervention Program ◽

Antimicrobial Prophylaxis ◽

Surgical Site Infections ◽

Control Program ◽

Post Discharge ◽

Post Intervention ◽

Successful Control ◽

A Prospective Study ◽

Government Reimbursement

OBJECTIVE: Describe implementation of a successful program to reduce doses (cefazolin 2 to 1 g) used for antimicrobial prophylaxis. METHODS: Evaluation of an intervention program to reduce prophylactic antimicrobial doses. The intervention included weekly staff discussions, automatic dispensation of 1g-vial of cefazolin by the pharmacy unless expressly requested by surgeon and increase in post-discharge surveillance as a strategy to reassure surgeons of the safety of the reduction. In the pre and post intervention periods, a prospective study of antimicrobial consumption and surgical site infections were measured. RESULTS: There were 5,164 and 5,204 deliveries in 2001-2002 and 2003-2004, respectively; 1,524 (29.5%) and 1,363 (26%) were cesarean sections. There was a 45% decrease in cefazolin vials used on average per cesarean section (2.29 to 1.25). Patients evaluated increased from 16% to 67% and the SSI rates in both periods were 3.34% to 2.42%, respectively. CONCLUSION: An ample intervention, including administrative and educational measures, led to high compliance with dose reduction and saved more than US$4,000 in cefazolin, considered important because government reimbursement in Brazil for cesarean section is $80.

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Insecticide Susceptibility Status of Aedes albopictus in Dengue Hotspot Areas in Malaysia

ASM Science Journal ◽

10.32802/asmscj.2020.558 ◽

2021 ◽

Vol 14 ◽

pp. 1-8

Author(s):

WAN FATMA ZUHARAH ◽

Ahmad Mohiddin ◽

Asmalia Md Lasim ◽

Zairi Jaal ◽

...

Keyword(s):

Insecticide Resistance ◽

Vector Control ◽

Aedes Albopictus ◽

Continuous Monitoring ◽

Reference Strain ◽

Control Program ◽

Aedes Mosquitoes ◽

Northern District ◽

Vector Control Program ◽

Susceptibility Status

The vector control program has become challenging due to the resistance problem occurs in Aedes mosquitoes. Aedes albopictus (Skuse, 1894) is the most dominant species contributing as a vector of dengue, Chikungunya and Zika viruses in Malaysia. Knowledge of the current insecticide resistance of Ae. albopictus is essential for the success of vector control program. Here, we reported the susceptibility status of Ae. albopictus collected from the dengue hotspot areas in the Northern District of Penang Island, Malaysia on three common use insecticides in vector control program. Aedes albopictus was sampled from three localities at Flat Hamna, Kampung Sungai Gelugor and Kampung Tanjung Tokong in the Northern District of Penang Island, Malaysia. The adult bioassay results suggested the Flat Hamna strain (FH) was found to develop incipient resistance after 24h exposure towards all three insecticides tested; permethrin, deltamethrin and malathion (mortality 97-87%). With 1.93 fold of Resistance Ratio 50 (RR50) values, FH strains have the highest chances to develop resistance towards permethrin. Among all insecticides tested, malathion was contributed to significantly higher KdT50 in all Ae. albopictus strains as compared to VCRU reference strain (p<0.001). Thus suggesting malathion insecticide is the least effective insecticide in our vector control program. Our finding can be used as a baseline for insecticide resistance of Ae. albopictus to improve vector control across Malaysia. Permethrin and deltamethrin are still reliable to be used in the control program, nonetheless require continuous monitoring on their susceptibility towards Ae. albopictus.

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Prevalence, Intensity of Soil-Transmitted Helminths, and Factors Associated with Infection: Importance in Control Program with Ivermectin and Albendazole in Eastern Côte d’Ivoire

Journal of Tropical Medicine ◽

10.1155/2019/7658594 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Agodio Loukouri ◽

Aboulaye Méité ◽

Olivier K. Kouadio ◽

Norbert N. Djè ◽

Gotré Trayé-Bi ◽

...

Keyword(s):

Control Program ◽

The Other ◽

Intestinal Helminths ◽

Open Defecation ◽

Soil Transmitted Helminths ◽

Lack Of Information ◽

Chi Squared ◽

Successful Control ◽

Stool Samples

Evaluation of soil-transmitted helminths (STHs) and implementation of additional interventions are required in the region of a filariasis control program, given that antifilariasis drugs also have a beneficial effect on STHs. Thus, this study determines the extensive epidemiology of STHs to improve their successful control. Stool samples were analyzed using the Kato-Katz method. Chi-squared and Kruskal-Wallis tests were used to measure differences in infection rates and intensities, respectively, and logistic regression identified the risks of infection. The main intestinal helminths (A. lumbricoides, hookworm [N. americanus],S. mansoni,andT. trichiura) were found in the population. The overall prevalence of STHs was 19.5%. The prevalence of hookworm, the predominant species, ranged from 2% (n=6) to 28% (n=97). The overall prevalence of the other intestinal helminths was less than 6% (n=18). Intensity of hookworm was mostly light with a range from 1.6% (n=5) to 25.9% (n=90). However, the intensity of the species was significantly greater in Soribadougou compared to the other localities. Heavy infection was found in old children and adults but not in young children. Open defecation (OR=3.23, p≤0.05), dog/cat raising (OR=1.94, p≤0.05), farming (OR=14.10, p≤0.05), and irrigated culture (OR=3.23, p≤0.05) were positively associated with hookworm. It was observed that the participants missed the follow-up examinations due to trip (32.7%) or misunderstanding (15%) and lack of information (11.8%) of the purpose of the survey. Thus, to sustain the control of STHs, the MDA program should target the entire community and add education about the use of toilets, best practices of farming, and dog/cat raising.

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A Biosecurity Response to Aedes albopictus (Diptera: Culicidae) in Auckland, New Zealand

Journal of Medical Entomology ◽

10.1093/jmedent/47.4.600 ◽

2010 ◽

Vol 47 (4) ◽

pp. 600-609 ◽

Cited By ~ 6

Author(s):

Peter Holder ◽

Sherly George ◽

Mark Disbury ◽

Monica Singe ◽

John M. Kean ◽

...

Keyword(s):

New Zealand ◽

Aedes Albopictus ◽

Large Scale ◽

Light Trapping ◽

Control Program ◽

Larval Habitat ◽

Habitat Modification ◽

Surveillance Program ◽

Founding Population ◽

Trace Back

Abstract A biosecurity response was triggered by the detection of Aedes albopictus (Skuse) (Diptera: Culicidae) at the Port of Auckland, New Zealand. Ae. albopictus does not occur in New Zealand and is the most significant mosquito threat to this country. The possibility that a founding population had established, resulted in a large-scale biosecurity surveillance and control program. The response was initiated in early March 2007 and completed by mid-May 2007. No further exotic mosquitoes were detected. The response surveillance program consisted of larval habitat surveys and high density ovi- and light trapping. It was coordinated with a habitat modification and S-methoprene treatment control program. The response policies were guided by analysis of surveillance and quality assurance data, population modeling, and trace-back activities. Mosquito habitat and activity close to port were both more abundant than expected, particularly in storm water drain sumps. Sumps are difficult to treat, and during the response some modification was required to the surveillance program and the control regime. We were assured of the absence or eradication of any Ae. albopictus population, as a result of nil detection from surveillance, backed up by four overlapping rounds of insecticide treatment of habitat. This work highlights the importance of port surveillance and may serve as a guide for responses for future urban mosquito incursions.

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Initial Evidence of Aedes Albopictus (Diptera: Culicidae) Domiciliation in Havana City, Cuba 1995-2018.

10.21203/rs.3.rs-63073/v1 ◽

2020 ◽

Author(s):

María del Carmen Marquetti Fernández ◽

Magaly Castillo ◽

Iris Peraza ◽

Maricely Milian ◽

Roberto Molina ◽

...

Keyword(s):

Urban Area ◽

Aedes Albopictus ◽

Control Program ◽

Sympatric Species ◽

Vacant Lots ◽

Entomological Monitoring ◽

Havana City ◽

National Control

Abstract Background. Various arboviruses are transmitted to humans by mosquitoes, particularly Aedes aegypti and Aedes albopictus, two invasive and frequently sympatric species. The objective of this study was to evaluate the behavior of Ae. albopictus with regards to houses and association with other mosquitoes in Havana province. Methods. All deposits containing water in the houses and vacant lots of urban and peri urban municipalities of the province Havana were sampled during two periods: the first 1995 – 1999 and the second 2010-2018. Results. Patterns in the presence of Ae. albopictus in the study area were observed: the persistent absence of Ae. albopictus in one municipality; in two municipalities, starting from an absence in the first period to a rapid dispersion in the following period; and a sustained decrease in the dispersion of Ae. albopictus in two other municipalities. The association of Ae. albopictus with other mosquitoes smaller in the peripheral municipalities, although being the ones with the greatest presence of Ae. albopictus. However overall, we found an increase in this association when comparing the period 2010-2018 with the first period since its introduction in Havana. Inside the houses, Ae albopictus was present in 8% (2016) to 21.5% (2013) with an average of 15%, which evidences an initial domiciliation of the species.Conclusions. The results obtained in this work show an initiation of domiciliation of Ae albopictus in the urban area of Havana province. This is important to alert the National Control Program to strengthen the entomological monitoring of Ae. albopictus, and not only Ae. aegypti. The follow up of this domiciliation is important to guide control efforts, knowing its role as a vector of different arboviruses.

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Integrated control of Aedes albopictus in Southwest Germany supported by the Sterile Insect Technique

Parasites & Vectors ◽

10.1186/s13071-021-05112-7 ◽

2022 ◽

Vol 15 (1) ◽

Author(s):

Norbert Becker ◽

Sophie Min Langentepe-Kong ◽

Artin Tokatlian Rodriguez ◽

Thin Thin Oo ◽

Dirk Reichle ◽

...

Keyword(s):

Aedes Albopictus ◽

Sterile Insect Technique ◽

Large Scale ◽

Integrated Control ◽

Control Program ◽

Control Area ◽

West Germany ◽

Mosquito Vector ◽

Breeding Sites ◽

South West

Abstract Background The invasive species Aedes albopictus, commonly known as the Asian tiger mosquito, has undergone extreme range expansion by means of steady introductions as blind passengers in vehicles traveling from the Mediterranean to south-west Germany. The more than 25 established populations in the State of Baden-Württemberg, Palatine and Hesse (south-west Germany) have become a major nuisance and public health threat. Aedes albopictus deserves special attention as a vector of arboviruses, including dengue, chikungunya and Zika viruses. In Germany, Ae. albopictus control programs are implemented by local communities under the auspices of health departments and regulatory offices. Methods The control strategy comprised three pillars: (i) community participation (CP) based on the elimination of breeding sites or improved environmental sanitation, using fizzy tablets based on Bacillus thuringiensis israelensis (fizzy Bti tablets; Culinex® Tab plus); (ii) door-to-door (DtD) control by trained staff through the application of high doses of a water-dispersible Bti granular formulation (Vectobac® WG) aimed at achieving a long-lasting killing effect; and (iii) implementation of the sterile insect technique (SIT) to eliminate remaining Ae. albopictus populations. Prior to initiating large-scale city-wide treatments on a routine basis, the efficacy of the three elements was evaluated in laboratory and semi-field trials. Special emphasis was given to the mass release of sterile Ae. albopictus males. Results More than 60% of the local residents actively participated in the first pillar (CP) of the large-scale control program. The most effective element of the program was found to be the DtD intervention, including the application of Vectobac® WG (3000 ITU/mg) to potential breeding sites (10 g per rainwater container, maximum of 200 l = maximum of approx. 150,000 ITU/l, and 2.5 g per container < 50 l) with a persistence of at least 3 weeks. In Ludwigshafen, larval source management resulted in a Container Index for Ae. albopictus of < 1% in 2020 compared to 10.9% in 2019. The mean number of Aedes eggs per ovitrap per 2 weeks was 4.4 in Ludwigshafen, 18.2 in Metzgergrün (Freiburg) (SIT area) and 22.4 in the control area in Gartenstadt (Freiburg). The strong reduction of the Ae. albopictus population by Bti application was followed by weekly releases of 1013 (Ludwigshafen) and 2320 (Freiburg) sterile Ae. albopictus males per hectare from May until October, resulting in a high percentage of sterile eggs. In the trial areas of Ludwigshafen and Frieburg, egg sterility reached 84.7 ± 12.5% and 62.7 ± 25.8%, respectively; in comparison, the natural sterility in the control area was 14.6 ± 7.3%. The field results were in line with data obtained in cage tests under laboratory conditions where sterility rates were 87.5 ± 9.2% after wild females mated with sterile males; in comparison, the sterility of eggs laid by females mated with unirradiated males was only 3.3 ± 2.8%. The overall egg sterility of about 84% in Ludwigshafen indicates that our goal to almost eradicate the Ae. albopictus population could be achieved. The time for inspection and treatment of a single property ranged from 19 to 26 min depending on the experience of the team and costs 6–8 euros per property. Conclusions It is shown that an integrated control program based on a strict monitoring scheme can be most effective when it comprises three components, namely CP, DtD intervention that includes long-lasting Bti-larviciding to strongly reduce Ae. albopictus populations and SIT to reduce the remaining Ae. albopictus population to a minimum or even to eradicate it. The combined use of Bti and SIT is the most effective and selective tool against Ae. albopictus, one of the most dangerous mosquito vector species. Graphical Abstract

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Initial Evidence of Aedes Albopictus (Diptera: Culicidae) Domiciliation in Havana City, Cuba 1995-2018.

10.21203/rs.3.rs-47909/v1 ◽

2020 ◽

Author(s):

María del Carmen Marquetti Fernández ◽

Magaly Castillo ◽

Iris Peraza ◽

Maricely Milian ◽

Roberto Molina ◽

...

Keyword(s):

Urban Area ◽

Aedes Albopictus ◽

Control Program ◽

Sympatric Species ◽

Vacant Lots ◽

Entomological Monitoring ◽

Havana City ◽

National Control

Abstract Background. Various arboviruses are transmitted to humans by mosquitoes, particularly Aedes aegypti and Aedes albopictus, two invasive and frequently sympatric species. The objective of this study was to evaluate the behavior of Ae. albopictus with regards to houses and association with other mosquitoes in Havana province. Methods. All deposits containing water in the houses and vacant lots of urban and peri urban municipalities of the province Havana were sampled during two periods: the first 1995 – 1999 and the second 2010-2018. Results. Patterns in the presence of Ae. albopictus in the study area were observed: the persistent absence of Ae. albopictus in one municipality; in two municipalities, starting from an absence in the first period to a rapid dispersion in the following period; and a sustained decrease in the dispersion of Ae. albopictus in two other municipalities. The association of Ae. albopictus with other mosquitoes smaller in the peripheral municipalities, although being the ones with the greatest presence of Ae. albopictus. However overall, we found an increase in this association when comparing the period 2010-2018 with the first period since its introduction in Havana. Inside the houses, Ae albopictus was present in 8% (2016) to 21.5% (2013) with an average of 15%, which evidences an initial domiciliation of the species.Conclusions. The results obtained in this work show an initiation of domiciliation of Ae albopictus in the urban area of Havana province. This is important to alert the National Control Program to strengthen the entomological monitoring of Ae. albopictus, and not only Ae. aegypti. The follow up of this domiciliation is important to guide control efforts, knowing its role as a vector of different arboviruses.

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Susceptibility Status of a Recently Introduced Population of Aedes albopictus to Insecticides Used by the Vector Control Program in Merida, Yucatan, Mexico

Journal of the American Mosquito Control Association ◽

10.2987/20-6937.1 ◽

2021 ◽

Vol 37 (3) ◽

pp. 164-168

Author(s):

Y. Contreras-Perera ◽

G. Gonzá lez-Olvera ◽

A. Che-Mendoza ◽

P. Mis-Avila ◽

J. Palacio-Vargas ◽

...

Keyword(s):

Vector Control ◽

Aedes Albopictus ◽

Control Strategies ◽

Mosquito Species ◽

Control Program ◽

Suburban Area ◽

Vector Control Program ◽

Control And Prevention ◽

Invasive Mosquito ◽

Established Population

ABSTRACT In recent years, Aedes albopictus has become the most important invasive mosquito species worldwide. In 2018, Ae. albopictus was found in a suburban area of Merida, one of the cities with the highest number of arbovirus cases in Mexico in the last 10 years. As Ae. albopictus continues its range expansion, there is a need to monitor its susceptibility to existing insecticide classes, since countries like Mexico currently do not consider Ae. albopictus in its insecticide management programs. In order to determine its susceptibility to the insecticides usually applied by the vector control program in Mexico, the Centers for Disease Control and Prevention bottle bioassays were performed on individuals from established population of Ae. albopictus from Merida, Yucatan, Mexico. Results suggested that the population recently found in the suburban area of Merida is susceptible to permethrin, deltamethrin, chlorpyrifos, malathion, bendiocarb, and propoxur. Further studies of insecticide resistance using biochemical and molecular tools together with more knowledge of the biology and ecology of this species are necessary to generate specific and efficient control strategies in Mexico.

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