A Case of Usefulness of Auto-Injectable Adrenaline as a Prophylactic Countermeasure Against Bee Sting for Forestry Workers.

Since 2015, the Ministry of Agriculture, Forestry and Fisheries in Japan has put in place regulations for forestry workers with bee or wasp allergies. These regulations allow workers to carry auto-injectable adrenaline when they engage in forestry work. A 48-year-old male worker identified as having a bee allergy was provided with an auto-injectable adrenaline prescription. The worker had experienced bee stings several times but never had an anaphylactic reaction. However, after suffering two bee stings to the head and face region, he developed an anaphylactic condition. He used the auto-injectable adrenaline on himself and was transported to an acute critical care center. The worker received additional injection of adrenaline at the health center for residual symptoms. The worker survived with no adverses outcome. The present study described the usefulness of prescribed auto-injectable adrenaline as a prophylactic countermeasure against bee stings for forestry workers with documented allergies. This framework may be useful for protecting forestry workers around the world.

Entomological Surveillance Planning Tool (ESPT)-generated actionable evidence on human and vector behaviours optimizes present interventions and reduces exposure to Anopheles vectors in two communities of Guna Yala, Panamá.

BACKGROUND: Although most of Panamá is free from malaria, localized foci of transmission persist, including in the Guna Yala region. Government-led entomological surveillance using an Entomological Surveillance Planning Tool (ESPT) sought to answer programmatically relevant questions on local entomological drivers of transmission and gaps in protection to guide local vector control decision-making. METHODS: The ESPT was used to design a sampling plan to answer priority programmatic questions about the appropriateness of Long Lasting Insecticidal Nets (LLINs) and spaces and times where humans remain exposed to Anopheles bites (gaps in protection) in the communities of Permé and Puerto Obaldía, Guna Yala. Adult Anopheles were sampled at three time points via human landing catches (HLCs) during the rainy and dry seasons (2018/2019). Human behaviour observations (HBOs) were conducted alongside HLCs to examine intervention use, indoor versus outdoor activity, and sleeping patterns. HLC and HBO data were integrated to evaluate HBO-adjusted human biting rate (HBR). RESULTS: A total of 7,431 adult Anopheles were collected across both sites. Of the 450 specimens molecularly confirmed to species-level, 75.5% (n = 340) were confirmed as Anopheles Nyssorhynchus albimanus, followed by Anopheles (Ny.) aquasalis. Anopheles host seeking activity was demonstrated to be primarily exophagic throughout all sampling periods and in both communities. When adjusted with HBOs, exposure to mosquito bites was predominantly indoors and overnight in Permé (Nov, Mar), compared to predominantly outdoors in Puerto Obaldía (Nov, Mar, Jul). Differences in site-specific human-vector exposure profiles were due to contrasting cultural and lifestyle practices between Permé and Puerto Obaldía (possibly partly influenced by the absence of electricity in Permé), and lower LLIN use in Permé. This evidence supported a previously planned LLIN campaign alongside a social behaviour change communication (SBCC) strategy in the Guna Yala Comarca (Jul 2019), which increased LLIN use. In turn, this led to a reduction of indoor exposure to mosquito bites, and a shift to predominant outdoor exposure to mosquito bites. CONCLUSION: ESPT-based question-driven planning and the integration of HBOs, intervention, and HLC data generated evidence towards answering the programmatic questions. This evidence enabled the characterization of site-specific human-vector exposure profiles, and the quantification of remaining gaps in protection. These data also provide important insights into remaining gaps in protection that must be addressed to further reduce human exposure to mosquito bites at these sites.

Spread of stinging ants to oceanic islands, and the need to raise awareness of prevention and treatment of ant stings.

OBJECTIVE: Venomous invasive ants are rapidly dispersing throughout oceanic islands. Medics unfamiliar with envenomation or venom-induced anaphylaxis may be unprepared for the range of possible reactions and corresponding treatments. We detail the suboptimal treatment of a patient suffering anaphylaxis from an ant sting on a remote island and describe what treatment should have been provided. METHODS: The patient experienced stings on his feet from an ant later identified as tropical fire ant, Solenopsis geminata. Clinical examination revealed throat swelling without obstruction of the airway or pharynx. RESULTS: The patient was provided the following suboptimal treatment: intravenously-administered antihistamine and saline perfusion. Injected epinephrine should be the standard first line of treatment for anaphylaxis, even when not all symptoms are present. CONCLUSION: A rise in invasive hymenopteran stings on oceanic islands is inevitable, and proactively improving public awareness and medical training could save lives.

Insect repellents: An updated review for the clinician.

Malaria, Zika virus, West Nile virus, Dengue fever, and Lyme disease are common causes of morbidity and mortality around the world. While arthropod bites may cause local inflammation and discomfort, a greater concern is the potential to develop deadly systemic infection. The use of insect repellents (IRs) to prevent systemic infections constitutes a fundamental public health effort. Cost effectiveness, availability, and high efficacy against arthropod vectors are key characteristics of an ideal IR. Currently, numerous IRs are available on the market, with N,N-diethyl-3-methylbenzamide (DEET) being the most widely used. DEET has an excellent safety profile and remarkable protection against mosquitoes and various other arthropods. Other Environmental Protection Agency-registered IR ingredients (eg, permethrin, picaridin, IR3535, oil of lemon eucalyptus, oil of citronella, catnip oil, and 2-undecanone) are alternative IRs of great interest because some of these ingredients have efficacies comparable to that of DEET. These alternative IRs possess low toxicity and favorable customer experiences in use (eg, cosmetically pleasant, naturally occurring). This review summarizes the currently available Environmental Protection Agency-registered IRs, including their origins, mechanisms of action, side effect profiles, and available formulations. This review will enable the clinician to select the best IR option to meet a patient's needs and provide the greatest protection from arthropod bites and their sequelae.

Establishment of a protocol for preventive vaccination against equine insect bite hypersensitivity.

Insect bite hypersensitivity (IBH) is a seasonal dermatitis of horses caused by IgE-mediated reactions to bites of Culicoides midges characterized by an imbalance of T-cell subsets. Iceland is free of the causative species but the prevalence of IBH in exported Icelandic horses is especially high. We have shown that intralymphatic (i.l.) vaccination with r-Culicoides allergens in Aluminum hydroxide (alum) and monophosphoryl lipid A (MPLA) adjuvants induces a desired Th1/regulatory T-cell response. The aim of this study was to compare i.l. to subcutaneous (s.c.) injection. Twelve healthy Icelandic horses were injected, i.l. or s.c., three times with four-week interval, using purified r-Culicoides allergens in alum/MPLA. Serum antibody levels and cytokine profile following in vitro re-stimulation of PBMC were analysed. Comparable allergen-specific IgG antibodies were induced following both routes of vaccinations. The antibodies showed similar capacity to block binding of IgE from IBH-affected horse to the allergens. Upon re-stimulation of PBMC, IL-10 was induced. Horses vaccinated i.l. produced more IFN-γ and less IL-4 as compared to the horses injected s.c., but the difference did not reach significance. It can be concluded that applying the simpler s.c. injection instead of i.l. to obtain a suitable immune response could be option in IBH immunotherapy.

Novel Use of Topical Ivermectin for the Prevention of Facial Insect Bites.

Options to prevent facial insect bites while sleeping are limited. Patients may prefer to avoid facial application of potentially neurotoxic insect repellants. Non-toxic “natural” repellants have limited efficacy, and netting may not be well-tolerated. Nightly facial application of 1% topical ivermectin (IVM) cream completely prevented overnight bites in 2 patients, both of whom reported recurrent bites after discontinuation, and a return to complete bite prevention after IVM resumption. Topical IVM may be an alternative facial mosquito bite prevention modality. J Drugs Dermatol. 2022;21(8):906-907. doi:10.36849/JDD.6432.

Observing the distribution of mosquito bites on humans to inform personal protection measures against malaria and dengue vectors.

BACKGROUND: Understanding mosquito biting behaviours is important for designing and evaluating protection methods against nuisance biting and mosquito-borne diseases (e.g. dengue, malaria and zika). We investigated the preferred biting sites by Aedes aegypti and Anopheles arabiensis on adult volunteers in standing or sleeping positions; and estimated the theoretical protection limits affordable from protective clothing or repellent-treated footwear. METHODS: Adult volunteers dressed in shorts and t-shirts were exposed to infection-free laboratory-reared mosquitoes inside screened chambers from 6am to noon (for day-biting Ae. aegypti) or 6pm to midnight (night-biting An. arabiensis). Attempted bites on different body parts were recorded. Comparative observations were made on same volunteers while wearing sandals treated with transfluthrin, a vapour-phase pyrethroid that kills and repels mosquitoes. RESULTS: An. arabiensis bites were mainly on the lower limbs of standing volunteers (95.9% of bites below the knees) but evenly-distributed over all exposed body surfaces when the volunteers were on sleeping positions (only 28.8% bites below knees). Ae. aegypti bites were slightly concentrated on lower limbs of standing volunteers (47.7% below knees), but evenly-distributed on sleeping volunteers (23.3% below knees). Wearing protective clothing that leave only hands and head uncovered (e.g. socks + trousers + long-sleeved shirts) could theoretically prevent 78-83% of bites during sleeping, and at least 90% of bites during non-sleeping hours. If the feet are also exposed, protection declines to as low as 36.3% against Anopheles. The experiments showed that transfluthrin-treated sandals reduced An. arabiensis by 54-86% and Ae. aegypti by 32-39%, but did not change overall distributions of bites. CONCLUSION: Biting by An. arabiensis and Ae. aegypti occur mainly on the lower limbs, though this proclivity is less pronounced in the Aedes species. However, when hosts are on sleeping positions, biting by both species is more evenly-distributed over the exposed body surfaces. High personal protection might be achieved by simply wearing long-sleeved clothing, though protection against Anopheles particularly requires covering of feet and lower legs. The transfluthrin-treated footwear can reduce biting risk, especially by An. arabiensis. These findings could inform the design and use of personal protection tools (both insecticidal and non-insecticidal) against mosquitoes and mosquito-borne diseases.

Less is more: repellent-treated fabric strips as a substitute for full screening of open eave gaps for indoor and outdoor protection from malaria mosquito bites.

BACKGROUND: Providing protection from malaria vector bites, both indoors and outdoors, is crucial to curbing malaria parasite transmission. Screening of house entry points, especially with incorporated insecticides, confers significant protection but remains a costly and labour-intensive application. Use of spatial repellents has shown promise in creating areas of protection in peri-domestic areas. METHODS: This study aimed at comparing the protection provided by transfluthrin-treated and untreated complete screens over open eave gaps with incomplete transfluthrin-treated eave strips as a potential replacement for a full screen. Human landing catches were implemented independently inside and outside an experimental hut under controlled semi-field conditions, with insectary-reared Anopheles arabiensis mosquitoes. RESULTS: The odds of a female mosquito finding a human volunteer indoors and attempting to bite were similar whether the eaves were completely open or there was an untreated fabric strip fixed around the eaves. However, when the eave gap was completely screened without insecticide, the odds of receiving a bite indoors were reduced by 70% (OR 0.30, 95% CI 0.20-0.47). Adding transfluthrin to the full screen, further increased the protection indoors, with the odds of receiving a bite reduced by 92% (0.08, 95% CI 0.04-0.16) compared to the untreated screen. Importantly, the same protection was conferred when only a narrow transfluthrin-treated fabric strip was loosely fixed around the eave gap (OR 0.07, 95% CI 0.04-0.13). The impact of the transfluthrin treatment on outdoor biting was correlated with evening temperatures during the experiments. At lower evening temperatures, a transfluthrin-treated, complete screen provided moderate and variable protection from bites (OR 0.62, 95% CI 0.37-1.03), whilst at higher evening temperatures the odds of receiving a bite outdoors was over four times lower in the presence of transfluthrin, on either a full screen (OR 0.22 95% 0.12-0.38) or a fabric strip (OR 0.25, 95% 0.15-0.42), than when no treatment was present. CONCLUSION: The findings suggest that transfluthrin-treated fabric strips can provide a substitute for complete eave screens. They are a simple, easy-to-handle tool for protecting people from malaria mosquito bites indoors and potentially around the house in climatic areas where evening and night-time temperatures are relatively high.

Taking the Bite out of Mosquito Bites: The Role of Perceived Risk.

The present study examined how dimensions of perceived risk contributed to mosquito avoidance behaviors in a flood-prone area. Mosquito avoidance behaviors were classified into proactive (i.e. used repellant sources) and withdrawal/reactive (i.e. reduced outside activities) behaviors. After controlling for level of mosquito bites, increased scores for above normal perceived risk were associated with withdrawal/reactive avoidance behaviors; whereas, increased scores for normal perceived risk were associated with proactive avoidance behaviors. Efforts to improve mosquito avoidance behaviors should distinguish the type of perceived risk and the type of avoidance behavior. Greater congruence between perceived risk (i.e. normal risk of mosquito-borne illnesses) and avoidance behaviors (i.e. planning avoidance behaviors) will increase the effectiveness of education programs for disease prevention.

Efficacy and safety of repellents marketed in Brazil against bites from Aedes aegypti and Aedes albopictus: A systematic review.

BACKGROUND: Dengue, Zika and Chikungunya viruses represent a serious public health problem. No evidence is available on the efficacy of repellents commercially available in Brazil. This systematic review assessed the efficacy and safety of products containing repellents commercially available in Brazil for protection against bites from Aedes aegypti and Aedes albopictus. METHODS: We performed a systematic review using the CENTRAL, MEDLINE, EMBASE, CINAHL, Web of Science, AMED, LILACS and Scopus databases. Randomized clinical trials and non-randomized clinical trials comparing topical repellent products registered with the Brazilian Health Surveillance Agency were included. Main outcomes of interest investigated were adverse effects, percentage repellency and protection time against bites. Pairs of reviewers selected the studies, extracted the data and evaluated the risk of bias. RESULTS: Sixteen studies were included. No adverse effects were reported by the studies. Against Ae. aegypti: protection time using DEET (10% and 20%-spray) was similar to IR3535 (10% and 20%-spray) and longer than citronella (5%-spray). DEET (25%-solution) had longer protection time than eucalyptus (25%-solution), while DEET (20%-lotion) had longer protection time than citronella (10%-lotion). There was no difference in protection time between herbal repellents. DEET (7% and 15%- spray) had higher percentage repellency compared to both icaridin (7%-spray) and IR3535 (20%-spray). Against Ae. albopictus: DEET (15%-spray) had a similar protection time to icaridin (20%-spray), but longer than citronella (10%-spray). CONCLUSION: DEET proved more effective than the other synthetic and natural repellents marketed in Brazil for protecting against bites from the mosquito species investigated. All repellents studied exhibited satisfactory safety profile.

The efficacy of insecticide-treated window screens and eaves against Anopheles mosquitoes: a scoping review.

BACKGROUND: Female mosquitoes serve as vectors for a host of illnesses, including malaria, spread by the Plasmodium parasite. Despite monumental strides to reduce this disease burden through tools such as bed nets, the rate of these gains is slowing. Ongoing disruptions related to the COVID-19 pandemic may also negatively impact gains. The following scoping review was conducted to examine novel means of reversing this trend by exploring the efficacy of insecticide-treated window screens or eaves to reduce Anopheles mosquito bites, mosquito house entry, and density. METHODS: Two reviewers independently searched PubMed, Scopus, and ProQuest databases on 10 July, 2020 for peer-reviewed studies using insecticide-treated screens or eaves in malaria-endemic countries. These articles were published in English between the years 2000-2020. Upon collection, the reports were stratified into categories of biting incidence and protective efficacy, mosquito entry and density, and mosquito mortality. RESULTS: Thirteen out of 2180 articles were included in the final review. Eaves treated with beta-cyfluthrin, transfluthrin or bendiocarb insecticides were found to produce vast drops in blood-feeding, biting or mosquito prevalence. Transfluthrin-treated eaves were reported to have greater efficacy at reducing mosquito biting: Rates dropped by 100% both indoors and outdoors under eave ribbon treatments of 0.2% transfluthrin (95% CI 0.00-0.00; p < 0.001). Additionally, co-treating window screens and eaves with polyacrylate-binding agents and with pirimiphos-methyl has been shown to retain insecticidal potency after several washes, with a mosquito mortality rate of 94% after 20 washes (95% CI 0.74-0.98; p < 0.001). CONCLUSIONS: The results from this scoping review suggest that there is value in implementing treated eave tubes or window screens. More data are needed to study the longevity of screens and household attitudes toward these interventions.

Transfluthrin eave-positioned targeted insecticide (EPTI) reduces human landing rate (HLR) of pyrethroid resistant and susceptible malaria vectors in a semi-field simulated peridomestic space.

BACKGROUND: Volatile pyrethroids (VPs) are proven to reduce human-vector contact for mosquito vectors. With increasing resistance to pyrethroids in mosquitoes, the efficacy of VPs, such as transfluthrin, may be compromised. Therefore, experiments were conducted to determine if the efficacy of transfluthrin eave-positioned targeted insecticide (EPTI) depends on the resistance status of malaria vectors. METHODS: Ribbons treated with 5.25 g transfluthrin or untreated controls were used around the eaves of an experimental hut as EPTI inside a semi-field system. Mosquito strains with different levels of pyrethroid resistance were released simultaneously, recaptured by means of human landing catches (HLCs) and monitored for 24-h mortality. Technical-grade (TG) transfluthrin was used, followed by emulsifiable concentrate (EC) transfluthrin and additional mosquito strains. Generalized linear mixed models with binomial distribution were used to determine the impact of transfluthrin and mosquito strain on mosquito landing rates and 24-h mortality. RESULTS: EPTI treated with 5.25 g of either TG or EC transfluthrin significantly reduced HLR of all susceptible and resistant Anopheles mosquitoes (Odds Ratio (OR) ranging from 0.14 (95% Confidence Interval (CI) [0.11-0.17], P < 0.001) to 0.57, (CI [0.42-0.78] P < 0.001). Both TG and EC EPTI had less impact on landing for the resistant Anopheles arabiensis (Mbita strain) compared to the susceptible Anopheles gambiae (Ifakara strain) (OR 1.50 [95% CI 1.18-1.91] P < 0.001) and (OR 1.67 [95% CI 1.29-2.17] P < 0.001), respectively. The EC EPTI also had less impact on the resistant An. arabiensis (Kingani strain) (OR 2.29 [95% CI 1.78-2.94] P < 0.001) compared to the control however the TG EPTI was equally effective against the resistant Kingani strain and susceptible Ifakara strain (OR 1.03 [95% CI 0.82-1.32] P = 0.75). Finally the EC EPTI was equally effective against the susceptible An. gambiae (Kisumu strain) and the resistant An. gambiae (Kisumu-kdr strain) (OR 0.98 [95% CI 0.74-1.30] P = 0.90). CONCLUSIONS: Transfluthrin-treated EPTI could be useful in areas with pyrethroid-resistant mosquitoes, but it remains unclear whether stronger resistance to pyrethroids will undermine the efficacy of transfluthrin. At this dosage, transfluthrin EPTI cannot be used to kill exposed mosquitoes.

Simplified binomial estimation of human malaria transmission exposure distributions based on hard classification of where and when mosquitoes are caught: statistical applications with off-the-shelf tools.

The impacts and limitations of personal protection measures against exposure to vectors of malaria and other mosquito-borne pathogens depend on behavioural interactions between humans and mosquitoes. Therefore, understanding where and when they overlap in time and space is critical. Commonly used approaches for calculating behaviour-adjusted estimates of human exposure distribution deliberately use soft classification of where and when people spend their time, to yield nuanced and representative distributions of mean exposure to mosquito bites across entire human populations or population groups. However, these weighted averages rely on aggregating individual-level data to obtain mean human population distributions across the relevant behavioural classes for each time increment, so they cannot be used to test for variation between individuals. Also, these summary outcomes are quite complex functions of the disaggregated data, so they do not match the standard binomial or count distributions to which routine off-the-shelf statistical tools may be confidently applied. Fortunately, the proportions of exposure to mosquito bites that occur while indoors or asleep can also be estimated in a simple binomial fashion, based on hard classification of human location over a given time increment, as being either completely indoors or completely outdoors. This simplified binomial approach allows convenient analysis with standard off-the-shelf logistic regression tools, to statistically assess variations between individual humans, human population subsets or vector species. Such simplified binomial estimates of behavioural interactions between humans and mosquitoes should be more widely used for estimating confidence intervals around means of these indicators, comparing different vector populations and human population groups, and assessing the influence of individual behaviour on exposure patterns and infection risk. Also, standard sample size estimation techniques may be readily used to estimate necessary minimum experimental scales and data collection targets for field studies recording these indicators as key outcomes. Sample size calculations for field studies should allow for natural geographic variation and seasonality, taking advantage of rolling cross-sectional designs to survey and re-survey large numbers of separate study locations in a logistically feasible manner.

Effect of Different Wall Surface Coverage With Deltamethrin-Treated Netting on the Reduction of Indoor-Biting Anopheles Mosquitoes (Diptera: Culicidae).

Indoor residual spray with deltamethrin remains the most common tool for reducing malaria transmission in Thailand. Deltamethrin is commonly used to spray the entire inner surfaces of the walls to prevent mosquitoes from resting. This study compared the mosquito landing responses on humans inside three experimental huts treated with deltamethrin at three different extents of wall coverage (25%, 50%, and full coverage), with one clean/untreated hut serving as a control. There were no significant differences between the numbers of Anopheles mosquitoes landing in the 50% and full coverage huts, whereas, in comparison to both of these, there was a significantly greater number landing in the 25% coverage hut. This study demonstrates that varying the percent coverage of indoor surfaces with deltamethrin-treated netting influences the blood-feeding success of wild Anopheles, and our findings suggest that it may be possible to reduce the extent of insecticide surface treatment while maintaining equivalent mosquito avoidance action to that seen in fully treated structures.

Insect vectors' saliva and gut microbiota as a blessing in disguise: probability versus possibility.

Drawing of host blood is a natural phenomenon during the bite of blood-probing insect vectors. Along with the blood meal, the vectors introduce salivary components and a trail of microbiota. In the case of infected vectors, the related pathogen accompanies the aforementioned biological components. In addition to Anopheles gambiae or Anopheles stephensi, the bites of other nonmalarial vectors cannot be ignored in malaria-endemic regions. Similarly, the bite incidence of Phlebotomus papatasi cannot be ignored in visceral leishmaniasis-endemic regions. Even the chances of getting bitten by uninfected vectors are higher than the infected vectors. We have discussed the probability or possibility of uninfected, infected, and/or nonvector's saliva and gut microbiota as a therapeutic option leading to the initial deterrent to pathogen establishment.

Knowledge, attitudes and practices on African tick bite fever of rural livestock communities living in a livestock-wildlife interface area in the Eastern Cape Province of South Africa.

BACKGROUND: African tick bite fever (ATBF) caused by Rickettsia africae and transmitted by Amblyomma spp. ticks is one of the zoonotic tick-borne fevers from the spotted fever group (SFG) of rickettsiae, which is an emerging global health concern. There is paucity of information regarding the occurrence and awareness of the disease in endemic rural livestock farming communities living in livestock-wildlife interface areas in South Africa. METHODS: The purpose of the study was to assess the level of knowledge, attitudes and practices on ticks and ATBF infection from a community living in livestock-wildlife interface areas in South Africa. A focus group discussion (FGD) was carried out followed by verbal administration of a standardized semi-structured questionnaire a month later to 38 rural livestock farmers (23 from Caquba area and 15 from Lucingweni area where A. hebraeum was absent). An FGD was conducted in Caquba (situated at the livestock-wildlife interface where Amblyomma hebraeum was prevalent on cattle and infected with Rickettsia africae) in the O.R. Tambo district of the Eastern Cape province of South Africa. RESULTS: Results from the FGD and questionnaire survey showed that participants from the two rural communities were not aware of ATBF and were not aware that ticks are vectors of the disease. Respondents from Caquba reported of having frequent exposure to tick bites (91.3%, 21/23) specifically from the anthropophilic A. hebrauem which they were able to identify as Qwelagqibe in IsiXhosa (their vernacular). Thirteen out of 15 (86.7%) of respondents from Lucingweni reported that they had never been bitten by ticks, which corresponded with the absence of A. hebraeum from their locality as evidenced from results of a concurrent study on prevalence of ticks on livestock in the area. Both communities confirmed to being "very concerned" of tick bites and we presume this was more related to the localized wounds from the bites than to the diseases transmitted by the ticks. CONCLUSIONS: We recommend future studies encompassing seroprevalence of ATBF in Caquba and other communities at risk in South Africa including establishing surveillance systems to monitor the seasonal infection rates in ticks, cattle and humans.

Review of Issues on Residual Malaria Transmission.

Residual malaria transmission is the actual maintained inoculation of Plasmodium, in spite of a well-designed and implemented vector control programs, and is of great concern for malaria elimination. Residual malaria transmission occurs under several possible circumstances, among which the presence of exophilic vector species, such as Anopheles dirus, or indoor- and outdoor-biting vectors, such as Anopheles nili, or specific behavior, such as feeding on humans indoors, then resting or leaving the house the same night (such as Anopheles moucheti) or also changes in behavior induced by insecticides applied inside houses, such as the well-known deterrent effect of permethrin-treated nets or the irritant effect of DDT. The use of insecticides may change the composition of local Anopheles populations, such as A. arabiensis taking up the place of A. gambiae in Senegal, A. aquasalis replacing A. darlingi in Guyana, or A. harrisoni superseding A. minimus in Vietnam. The change in behavior, such as biting activity earlier than usually reported-for example, Anopheles funestus after a large-scale distribution of long-lasting insecticidal nets-or insecticide resistance, in particular the current spread of pyrethroid resistance, could hamper the efficacy of classic pyrethroid-treated long-lasting insecticidal nets and maintained transmission. These issues must be well documented in every situation to elaborate, implement, monitor, and evaluate tailored vector control programs, keeping in mind that they must be conceived as integrated programs with several well and appropriately coordinated approaches, combining entomological but also parasitological, clinical, and social methods and analyses. A successful integrated vector control program must then be designed to reduce transmission and incidence rates of malaria morbidity and overall mortality.

Fighting mosquito bite during a crisis: capabilities of Florida mosquito control districts during the COVID-19 pandemic.

BACKGROUND: The stay-at-home orders imposed in early April 2020 due to the COVID-19 pandemic in various states complicated mosquito control activities across the United States (US), and Florida was no exception. Mosquito control programs are the first line of defense against mosquito-borne pathogens. The purpose of this study was to examine the capabilities of Florida mosquito programs to implement key mosquito measures during the COVID-19 pandemic lockdown. METHODS: Using a self-administered online survey, we examined the capabilities of all Florida mosquito control programs (both state-approved mosquito districts, N = 63; and open programs, N = 27) at a time when the state of Florida was still under heightened awareness of, stay-at-home orders and planning a phase 1 reopening over the COVID-19 pandemic (June to July 2020). The final sample included mosquito control programs structured as the Board of County Commissioners (BOCC) (n = 42), independent tax district (n = 16), municipal (n = 10), and health or emergency department (n = 5). We used descriptive statistics to summarize information about the characteristics of responding programs, their implemented mosquito control and surveillance activities.  wWe used bivariate analysis to compare the characteristics of responding programs and the self-reported mosquito measures. RESULTS: Of the recruited mosquito control programs, 73 completed the survey (81.1% response rate; 73/90). Of these, 57.5% (n = 42) were Board of County Commissioners (BOCC) mosquito control programs, 21.9% (n = 16) were independent tax district programs, 13.7% (n = 10) were municipal mosquito control programs, and only 6.8% (n = 5) were either health or emergency department mosquito control programs. Except for arbovirus surveillance, most programs either fully or partially performed larval (61.8%) and adult (78.9%) surveillance; most programs conducted species-specific control for Aedes aegypti (85.2%, n = 54), Aedes albopictus (87.3%, n = 55), Culex quinquefasciatus (92.1%, n = 58), and Culex nigripalpus (91.9%, n = 57). CONCLUSIONS: Findings underscore the importance of ongoing mosquito control activities, and suggest that Florida mosquito control programs are vigilant and have significant capability to handle potential mosquito-borne disease threats, but arbovirus surveillance systems (laboratory testing of mosquito pools and testing of human and nonhuman specimens for arboviruses) are needed during pandemics as well.