Drug Resistance in Filarial Parasites Does Not Affect Mosquito Vectorial Capacity

Parasite drug resistance presents a major obstacle to controlling and eliminating vector-borne diseases affecting humans and animals. While vector-borne disease dynamics are affected by factors related to parasite, vertebrate host and vector, research on drug resistance in filarial parasites has primarily focused on the parasite and vertebrate host, rather than the mosquito. However, we expect that the physiological costs associated with drug resistance would reduce the fitness of drug-resistant vs. drug-susceptible parasites in the mosquito wherein parasites are not exposed to drugs. Here we test this hypothesis using four isolates of the dog heartworm (Dirofilaria immitis)—two drug susceptible and two drug resistant—and two vectors—the yellow fever mosquito (Aedes aegypti) and the Asian tiger mosquito (Ae. albopictus)—as our model system. Our data indicated that while vector species had a significant effect on vectorial capacity, there was no significant difference in the vectorial capacity of mosquitoes infected with drug-resistant vs. drug-susceptible parasites. Consequently, contrary to expectations, our data indicate that drug resistance in D. immitis does not appear to reduce the transmission efficiency of these parasites, and thus the spread of drug-resistant parasites in the vertebrate population is unlikely to be mitigated by reduced fitness in the mosquito vector.

Download Full-text

From the Field to the Laboratory: Quantifying Outdoor Mosquito Landing Rate to Better Evaluate Topical Repellents

Journal of Medical Entomology ◽

10.1093/jme/tjaa298 ◽

2021 ◽

Author(s):

Mara Moreno-Gómez ◽

Rubén Bueno-Marí ◽

Andrea Drago ◽

Miguel A Miranda

Keyword(s):

World Health ◽

Asian Tiger Mosquito ◽

Personal Protection ◽

Evaluation Standards ◽

Testing Conditions ◽

Vector Borne Diseases ◽

Asian Tiger ◽

The World ◽

Vector Borne ◽

Health Organization

Abstract Vector-borne diseases are a worldwide threat to human health. Often, no vaccines or treatments exist. Thus, personal protection products play an essential role in limiting transmission. The World Health Organization (WHO) arm-in-cage (AIC) test is the most common method for evaluating the efficacy of topical repellents, but it remains unclear whether AIC testing conditions recreate the mosquito landing rates in the field. This study aimed to estimate the landing rate outdoors, in an area of Europe highly infested with the Asian tiger mosquito (Aedes albopictus (Skuse, 1894, Diptera: Culididae)), and to determine how to replicate this rate in the laboratory. To assess the landing rate in the field, 16 individuals were exposed to mosquitoes in a highly infested region of Italy. These field results were then compared to results obtained in the laboratory: 1) in a 30 m3 room where nine volunteers were exposed to different mosquito abundances (ranges: 15–20, 25–30, and 45–50) and 2) in a 0.064 m3 AIC test cage where 10 individuals exposed their arms to 200 mosquitoes (as per WHO requirements). The highest mosquito landing rate in the field was 26.8 landings/min. In the room test, a similar landing rate was achieved using 15–20 mosquitoes (density: 0.50–0.66 mosquitoes/m3) and an exposure time of 3 min. In the AIC test using 200 mosquitoes (density: 3,125 mosquitoes/m3), the landing rate was 229 ± 48 landings/min. This study provides useful reference values that can be employed to design new evaluation standards for topical repellents that better simulate field conditions.

Download Full-text

Investigation on the virologic vector-borne diseases by mosquito vector in Yeongnam, Korea

Entomological Research ◽

10.1111/j.1748-5967.2011.00399.x ◽

2011 ◽

Vol 41 (6) ◽

pp. 286-286

Author(s):

Heeju Hwang ◽

SeWon Kang ◽

ByungUn No ◽

Dongkyu Lee ◽

WookGyo Lee ◽

...

Keyword(s):

Mosquito Vector ◽

Vector Borne Diseases ◽

Vector Borne

Download Full-text

Resistance at No Cost: The Transmissibility and Potential for Disease Progression of Drug-ResistantM. Tuberculosis

10.1101/475764 ◽

2018 ◽

Cited By ~ 2

Author(s):

Mercedes C. Becerra ◽

Chuan-Chin Huang ◽

Leonid Lecca ◽

Jaime Bayona ◽

Carmen Contreras ◽

...

Keyword(s):

Drug Resistance ◽

Drug Resistant ◽

Resistance Mutations ◽

Pulmonary Tb ◽

Genetic Fingerprint ◽

Resistant Tuberculosis ◽

Significant Difference ◽

Mdr Tb ◽

The Impact

AbstractBackgroundThe future trajectory of drug resistant tuberculosis strongly depends on the fitness costs of drug resistance mutations. Here, we measured the association of phenotypic drug resistance and the risk of TB infection and disease among household contacts (HHCs) of patients with pulmonary TB.MethodsWe evaluated 12767 HHCs of patients with drug sensitive and resistant pulmonary TB at baseline, two, six, and 12 months to ascertain infection status and to determine whether they developed tuberculosis disease. We also assessed the impact of drug resistance phenotype on the likelihood that a TB strain shared a genetic fingerprint with at least one other TB patient in the cohort.FindingsAmong 3339 TB patients for whom were DST available, 1274 (38%) had TB that was resistant to at least one drug and 478 (14⋅3%) had multi-drug resistant (MDR) TB, i.e. TB resistant to both INH and rifampicin. Compared to HHCs of drug sensitive TB patients, those exposed to a patient with MDR-TB had an 8% (95% CI: 4-13%) higher risk of infection by the end of follow up. We found no statistically significant difference in the relative hazard of incident TB disease among HHCs exposed to MDR-TB compared to DS-TB (Adjusted HR 1⋅28 [(95% CI: ⋅9-1⋅83]). Patients with MDR-TB were more likely to be part of a genetic cluster than were DS-TB patients.InterpretationClinical strains of MDR M. tuberculosis are neither less transmissible than drug sensitive strains nor less likely to cause disease. (ClinicalTrials.gov number,NCT00676754)FundingNational Institutes of Health: NIH/NIAID CETR U19AI109755StatementAll authors have seen the manuscript and approved the manuscript.

Download Full-text

Community Perception Regarding Mosquito-Borne Diseases in Some Selected Areas of Ganjam District of Odisha State, India

International Quarterly of Community Health Education ◽

10.1177/0272684x211004943 ◽

2021 ◽

pp. 0272684X2110049

Author(s):

Sisir K Nayak ◽

Surya N Swain ◽

T Sarita Achari ◽

Tapan K Barik

Keyword(s):

Disease Incidence ◽

Basic Knowledge ◽

Health Concern ◽

Mosquito Vector ◽

College Level ◽

Community Perception ◽

Vector Borne Diseases ◽

Vector Population ◽

Vector Borne ◽

Ganjam District

Mosquito-borne diseases are a major public health concern. Because of absence of effective therapy and vaccination to treat and prevent such vector-borne diseases, these initial cases have triggered strong concerns within medical communities, turning a bad dream into reality. To date, reducing the mosquito vector population remains the main strategy to control the transmission of mosquito borne diseases. In this connection, community-based perception recognized as an essential tool for long-term vector control management. In this study, a community perception survey was carried out in six selected study areas of Ganjam district of Odisha. A total of 3257 inhabitants from randomly chosen 600 no. of houses from 06 selected study areas were interviewed using a pre-tested structured questionnaire about various mosquito vector-borne diseases. As an outcome, we found that only 36% of people have basic knowledge and idea about vector-borne diseases, out of which only 14% know Anopheles as a causative agent whereas Aedes and Culex were very least concern. Regarding the source of knowledge, electronic media was the principal source of information, while the involvements of health personnel were least mentioned. Results of the current study indicates the necessity to plan health education program to bring important perceptions regarding vector-borne diseases at school and college level because the infrequent source of knowledge is the main cause of an increase in the disease incidence.

Download Full-text

Young and Old Sugar Apple (Annona squamosa Linn) Leaf Extracts As an Aedes aegypti Larva Insecticide

Medical Laboratory Technology Journal ◽

10.31964/mltj.v0i0.231 ◽

2019 ◽

Author(s):

Abdul Khair ◽

Noraida Noraida

Keyword(s):

Aedes Aegypti ◽

Leaf Extract ◽

Hemorrhagic Fever ◽

Control Group ◽

Leaf Extracts ◽

Control Group Design ◽

Vector Borne Diseases ◽

Apple Leaves ◽

Significant Difference ◽

Vector Borne

Vector-borne diseases are still a health problem in some tropical countries. One vector-borne disease is Dengue Hemorrhagic Fever (DHF). DHF never decreases and even tends to continue to increase, and many cause deaths in children, 90% of them attack children under 15 years. DHF cases in 2018 amounted to 65,602 cases, with 467 deaths (CFR = 0.71%). The behavior of holding water in various places such as tubs and tendons indirectly creates a breeding place for Aedes aegypti mosquitoes. The use of chemicals as insecticides can cause the death of non-target animals, environmental pollution, and the occurrence of vector resistance to insecticides. Therefore it is necessary to do other methods including the use of vegetable insecticides. Sugar apple leaves can be used to kill Aedes aegypti larvae. Sugar apple leaves will obtain throughout the year. The purpose of this study is to know the ability of young and old sugar apple leaves to kill Aedes aegypti larvae. This type of research is a posttest only control group design. The study sample was part of the Aedes aegypti larvae on the final instar III. The experiment to kill Aedes aegypti larvae use two types of sugar apple leaf extract, namely young and old sugar apple leaves with nine treatments four replications. Each treatment consisted of 25 larvae. The research results show There was no significant difference in the number of dead larvae using either extracts from young sugar apple leaves or old sugar apple leaves. LC90 of sugar apple leaf extract was between 0.05632 to 0.08324% and the effective residual age at LC90 (0.06568%) with the death of Aedes aegypti larvae was 92% over 24 hours (1 day).

Download Full-text

Short communication: New report of Aedes albopictus in Souk Ahras, Northeast Algeria

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d220742 ◽

2021 ◽

Vol 22 (7) ◽

Author(s):

Kaouther Hamaidia ◽

Noreddine Soltani

Keyword(s):

Aedes Albopictus ◽

Short Communication ◽

Asian Tiger Mosquito ◽

Breeding Sites ◽

Vector Borne Diseases ◽

Asian Tiger ◽

Mosquito Breeding ◽

Vector Borne ◽

The City ◽

Residential Garden

Abstract. Hamaidia K, Soltani N. 2021. Short communication: New report of Aedes albopictus in Souk Ahras, Northeast Algeria. Biodiversitas 22: 2901-2906. The present paper reports the occurrence of Aedes albopictus (Skuse), an aggressive Asian tiger mosquito in the city of Souk-Ahras (Northeast of Algeria). A “26 April” estate’ inhabitants (Souk-Ahras province) have reported unusual daytime bites by a striped mosquito. On early September 2020, an intensive field inspection was carried out for potential mosquito breeding sites in the locations around the city. A total of 105 specimens (8 larvae, 24 pupae and 73 adults) of Ae. albopictus were collected in a pile of old tyres in a residential garden. After previous records of this species in Algeria, this is the first evidence of its presence in Souk-Ahras province, and the findings enhance combined public participation with professional validation in surveillance of vector borne-diseases programs with emphasis on the need for sensitising citizens about controlling this important vector.

Download Full-text

Expression of MicroRNA of Macrophages Infected with Attenuated Leishmania major Parasite

Journal of Pediatric Infectious Diseases ◽

10.1055/s-0041-1724021 ◽

2021 ◽

Vol 16 (03) ◽

pp. 106-110

Author(s):

Mohammad Hossein Feiz Haddad ◽

Hossein Rezvan ◽

Alireza Nourian ◽

Habib Habibpour

Keyword(s):

Real Time ◽

Leishmania Major ◽

Host Cells ◽

Control Group ◽

Vector Borne Diseases ◽

Intracellular Parasites ◽

Significant Difference ◽

Infected Cells ◽

Vector Borne

Abstract Objective Leishmaniasis has been proposed as one of the neglected vector-borne diseases due to an obligate intracellular parasite of the genus Leishmania. MicroRNAs (miRNAs) with a length of 22-nucleotide are known as the noncoding small RNAs. MiRNAs contribute to many biological and cellular approaches. Therefore, the present study evaluated expressing mmu-miR-721, mmu-miR-294–3p, mmu-miR-155–3p, and mmu-miR-30a in murine macrophages infected with attenuated Leishmania major parasites on 3 days after infection. Methods Attenuated promastigotes have been achieved after 20 passages of Leishmania major parasites. Cell line J774A.1 (murine macrophage) has been used for in vitro experiments. The stationary phase of attenuated L. major promastigotes has been chosen to infect the cells, and then their incubation has been performed with 5% CO2 at 37°C for 3 days. The real-time polymerase chain reaction (PCR) has also been performed with SYBR Green master-mix Kit for measuring the level of mmu-miR-721, mmu-miR-294–3p, mmu-miR-30a, and mmu-miR-155-3p expression. Uninfected macrophages have been considered as a control group. Results Real-time PCR demonstrated overexpression of mmu-miR-155-3p, mmu-miR-294–3p, and, mmu-miR-721 in the infected cells with Leishmania parasites after 3 days. Results showed no statistically significant difference in the mmu-miR-30a expression between infected macrophages and the uninfected control group. Conclusion Our findings suggested the significant contribution of the alterations in the miRNA levels to the regulation of macrophage functions following the creation of intracellular parasites like Leishmania. These data could help to understand better the genes' expression in the host cells in the course of leishmaniasis.

Download Full-text

Global Warming and Vector-borne Infectious Diseases

Journal of Disaster Research ◽

10.20965/jdr.2008.p0105 ◽

2008 ◽

Vol 3 (2) ◽

pp. 105-112 ◽

Cited By ~ 11

Author(s):

Mutsuo Kobayashi ◽

◽

Osamu Komagata ◽

Naoko Nihei

Keyword(s):

Global Warming ◽

Infectious Diseases ◽

Heat Waves ◽

Blood Feeding ◽

Mosquito Vector ◽

Vector Borne Diseases ◽

Extreme Climate ◽

Ipcc Report ◽

Vector Borne ◽

Global Mean Sea Level

Vector-borne diseases result from infections transmitted to humans by blood-feeding arthropods such as mosquitoes, ticks, and fleas. Such cold-blooded animals are influenced by environmental change. A recent IPCC report clearly showed that the emission of greenhouse gases has already changed world climates. Heat waves in Europe, rises in global mean sea level, summer droughts and wild fires, more intense precipitation, and increasing numbers of large cyclones and hurricanes may be typical example of extreme climate phenomena related to global warming. High temperatures may increase survival among arthropods, depending on their vector, behavior, ecology, and valuable factors, and temperate zone warming may accelerate the spread of mosquitoes such asAedes albopictus. The MIROK (K1) Model clearly shows a northern limit forAe.albopictus, particularly in northern Honshu in 2035 and southern and middle Hokkaido Island in 2100 in Japan. The spread of the mosquito vector through global used-tire trading in recent decades to Africa, the Mideast, Europe, and North and South America caused an outbreak of Chikungunya fever in north Italy in 2007. Global warming, extreme climate change, changing physical distribution, and an increase in oversea travel are also expected to influence the epidemiology of vector-borne infectious diseases.

Download Full-text