Mosquito Borne-Diseases and Their Management

Mosquitoes are known as one of the fatal living organisms in the world acting as vectors (living organisms that can transmit infectious diseases between humans or from animals to humans) for different diseases. Their ability to transmit and disseminate disease to humans causes millions of deaths every year. Malaria alone caused 4,38,000 deaths in 2015. The global occurrence of dengue has risen 30-times in the past 30 years, and more countries are reporting their first outbreaks of the disease NIOSH.

Apart from all the strategies and controlling measures, mosquito-borne diseases are dispersing world-widely responsible for the high toll of children and adolescent mortality and morbidity globally White et al.. Malaria, Yellow Fever, Dengue Fever, West Nile virus, Rift Valley Fever, Chikungunya, Japanese Encephalitis, Venezuelan Equine Encephalitis, and Murray Valley Encephalitis are common names of some important diseases caused by mosquitoes. MZC. Mosquito species corresponding to diseases can be described as Aedes Chikungunya Dengue fever Lymphatic filariasis Rift Valley fever. Surveillance conducted by concluded that the only mosquito species that seemed to be consistently infecting in the field with West Nile Virus was Culex pipiens species. It also demonstrated that the key to success for the survival and reproduction of Aedes albopictus was its behavior and biology. Its compensating breeding habits all its dispersant through travel and international trade.

Malaria is one of the deadliest mosquito-borne diseases 350 to 500 million cases annually. Lancet. Malaria is an infectious disease that causes fever, triggers chills, and a flu-like sickness. Within an incubation period of seven days or more after the acquisition of a pathogen from a mosquito bite, symptoms of the disease usually start to appear WHO.

Nanjesh KS et al. described from a surveillance study that 86% of his study subjects told that breeding site of mosquitoes is only polluted and stranded water, percentage of people who thought that malaria is transmitted by mosquitoes is 89.5%, 84.5% public told that rigor and fever are the most often symptoms of malarial infection and 65% of them used mosquito coil for prevention from mosquitoes.

Among the most common diseases transmitted by mosquitoes in the U.S, the West Nile Virus is at the top and the most common symptoms described are Body/Muscle aches, Fever, Headache, Fatigue, Joint pain, Rash, Stiff neck, and Paralysis CDC. Edmund G. Brown Jr. calculated that there were 6,030 cases of West Nile virus have been observed in California from 2003 to 2016.

Chikungunya fever is a sickness caused by viruses and spread by infected mosquitos' bite, these mosquitoes are active often in the daytime. The disease is similar to dengue fever and is characterized by severe, sometimes persistent, joint pain (arthritis), together with fever and rash WHO.

Dengue fever is the deadliest disease after malaria caused by the bite of infected mosquitoes. It is a viral disease caused by the dengue virus with four different serotypes. Each of the above-mentioned serotypes has the ability to cause and spread dengue fever and severe dengue fever (also known as dengue hemorrhagic fever) CHP.

Yellow fever is the most lethal viral infection (hemorrhagic fever) and before the discovery of any effective vaccine, it was the fearer to humans. There are around about 200 000 cases of illness reported with yellow fever and approximately 30 000 deaths occurred by yellow fever over the World. Over the past two decades, the number of cases of yellow has increased due to decreasing population immunity to infection, deforestation, urbanization, population movements and climate change WHO.

In this study, we will collect, manipulate and analyze all the obtained information related to mosquito-borne diseases and make a precise and achievable conclusion to stop and prevent the life-threatening and fast dispersion of these lethal diseases and to save the humans of underdeveloped countries which are suffering and combating poorly against these diseases.

Important Mosquito-Borne Diseases:

Aedes

• Chikungunya
• Dengue fever
• Lymphatic filariasis
• Rift Valley fever
• Yellow fever
• Zika

Anopheles

• Malaria
• Lymphatic filariasis

Culex

• Japanese encephalitis
• Lymphatic filariasis
• West Nile fever

WHO Response to Manage these Diseases:

The Global vector control response (GVCR) 2017–2030 permitted by the World Health Assembly provides planned direction to countries and progressing associates for the urgent establishment of vector control as an essential approach to prevent disease and actioning to epidemics. To achieve this, a re-building of vector control programs is compulsory, supported by amplified technical dimensions, improved organizations, reinforced monitoring and surveillance systems, and greater community mobilization. Ultimately, this will support the employment of an inclusive style to control vector that will enable the accomplishment of disease-specific national and global goals and contribute to the achievement of the supportable growth goals and universal health coverage.

WHO secretariat provides premeditated, normative, and technical supervision to countries and development partners for consolidation of vector control as a vital approach based on GVCR to prevent disease and actioning to outbreaks. Definitely, W.H.O. responds to vector-borne diseases by:

• Giving evidence-based direction for monitoring vectors and defending people against infection;
• providing technical support to countries so that they can efficiently manage cases and outbreaks;
• supporting countries to advance their reporting systems and capture the true burden of the disease;
• providing training on clinical management, diagnosis and vector control with some of its co-operating centres throughout the world;
• supporting the growth and evaluation of new tools, technologies and tactics for vector borne diseases, include vector control and disease management technologies.

A critical component in vector-borne diseases is interactive change. W.H.O. works with partners to deliver education and expand awareness so that people know how to protect themselves and their groups from mosquitoes, ticks, bugs, flies, and other vectors.

For many diseases such as Chagas disease, malaria, schistosomiasis, and leishmaniasis, W.H.O. has started control programs using funded or sponsored medicines. Availability to water and hygiene is a very vital factor in disease control and eradication. W.H.O works organized with many different government divisions to control these diseases.

Mosquitos Management Practices:

Introduction of Mosquito Predators:

Predation of mosquitoes by different living organisms is an important mechanism on which a great sort of literature is available. A survey is conducted by on predators of immature mosquitoes on the island of Kauai, Hawaii, in taro fields, the main larval mosquito habitat of Culex quinquefasciatus. According to his observations, mosquito-eating fish (Gambusia affinis and Poecilia reticulata) Copepods (Macrocyclops albidus Jurine), larvae of Odonata species, and aquatic insects, including backswimmers (Buenoa pallipes Fabricius) were the most-often detected predators. However, mosquito fish and backswimmers were found with variability from different locations while copepods were observed from all locations.

The present situation of insecticide resistance in mosquitoes and the impact of pesticides on non-target organisms have raised many questions across societies and compelled scientists to evaluate the alternative mechanisms to control malarial and other mosquito-borne disease vectors. Predation has been proposed as one of the vital regulation methods for malaria vectors in long-lasting aquatic habitats. He also found Anopheles gambiae DNA in at least three out of ten midguts of all predator species examined under his experiments. A predatory fish Gambusia affins seemed to be an efficient predator and is three times more effective than tadpole species in selected water bodies.

Martínez, H.Q. and Castro, A.R. reported that different living organisms were known to be active and efficient predators of mosquitoes. Mosquito-eating fish got a very crucial status among the predators of mosquitos and other invertebrates like hydras, from insects Muscidus scatophahgoides and Lispa ulginosa, several unknown species of aquatic hemipterans, and the predaceous diving beetle Eretes dytiscus. The mosquito genus Megarhinus is a very vital predator complex and worldwide often discussed as a most important biological agent (currently known as Toxorhynchites) and includes M. inornatus and M. splendens species. Previous literature includes bats even for control of adult mosquitoes.

The field and semi-field tests were conducted to check the efficacy and capacity of predatory fish on mosquito larvae and to test the influence of various types of chemical cues on the oviposition behavior of female mosquitoes. Data obtained from field trials, it was observed that there were fewer possibilities to find out culicine larvae, where the most common floodplain fish Tilapia guineensis often found. Though, the presence of any fish species was not concerned with the presence of anopheline larvae. In semi-field conditions both anopheline and culicine larvae are consumed by both T. guineensis and Epiplatys spilargyreius fish within 1d. Also, it seemed that ovipositing culicine females avoided the water areas where there were chances of the presence of fish. In contrast, there is not impact on oviposition behavior of anopheline females with the presence of fish.

Employing or announcing an auto-generating predator into the environment may offer sustained bio-control of pest populaces. Several predators of larvae of mosquito include amphibian tadpoles, dragonfly larvae, fish, mites, aquatic bugs, anostracans, malacostracans, copepods, cyclopoid,s and helminths. The most extensively used biological control agents of mosquito populaces are the western mosquito fish, Gambusia affinis, and the eastern mosquito fish, G. Holbrook. The impact of these fishes on the faunal structure and their incapability to live in small containers, tree holes, etc. which are perfect reproduction sites of important vectored mosquitoes, make them unfeasible and inefficient in regulating mosquito peoples.

Juliano, et al. concluded that predator impact on mosquito populaces sometimes rely on habitat structure and on the developing effects of many predators, predominantly interference amongst predators. Predators' nonfatal effects on mosquito oviposition, searching, and life history are common, and their values for populations and for the mosquito-borne disease are weakly understood.

The best-known method to control the mosquitos and stopping of lethal diseases is the use of mosquito predators as a way to eliminate the risk of human mortality. A predator of mosquitoes likely to be unknown in research is the dragonfly. Dragon fly immatures were seen to be present only in semi-permanent and alternating ponds. The results of tests recognized that dragonfly larvae were capable to eat large quantities of mosquito larvae in very short time, but the development rate of mosquitoes did not look like to be significantly influenced by dragonfly larvae. Ovipositing behavior of mosquitoes was not affected significantly by the presence or absence of dragonfly larvae. These results recommend that the presence of dragonfly larvae can play a vital role in the elimination of mosquito populations.

Another important predator Diplonychus indicus (Hemiptera: Belostomatidae) of dengue causing mosquito, Aedes aegypti (Diptera: Culicidae) attained great attention from a study by. His experiments described that when D. indicus was announced into the tires placed in the experimental garden, an extreme reduction of 95% and 98% respectively of late instars and pupae of Ae. aegypti was detected. But the tires placed in the control garden were not influenced. In different months of the year, the early instar larvae density of Ae. aegypti varied in the tires placed in both the gardens.

Dida et al. conducted a study investigating the baseline predation of young mosquitoes by large invertebrate predators along with Mara river to observe predator’s diversity, habitats of mosquito larvae, and ratio of their adaptive capacity to physio-chemical parameters of water. The impact of macroinvertebrate predator presence was correlated with water quality parameters and larval densities of mosquitoes using the Generalised Linear Model (GLM). Predators (n=297) from three orders of Hemiptera (54.2%), Odonata (22.9%), Coleoptera (22.9%) as mosquito larvae (n=4001) from 10 different species including An. gambiae s.l. (44.9%), Culex species (34.8%), An. coustani complex (13.8%), An. maculipalpis (3.6%), An. phronesis (1.2%), An. funestus group (0.5%), An. azaniae (0.4%), An. hamoni (0.3%), An. christyi (0.3%), An. ardensis (0.08%), An. faini (0.07%), An. sergentii (0.05%) and 0.05% of mosquitos from Aedes Spp. which could not be recognized to specie level due to lack of a particular key. These were captured from various habitats along the Mara River. It was also concluded that attacks on habitats by large invertebrate predators was carried out by the stimulation of the presence of mosquito larvae (pToxorhynchites, a type of mosquito with intraspecies predating larvae, has paid much attention as bio-control agents. Specific types of Toxorhynchites mosquitoes are very helpful for the control of Ae. aegypti because they reproduce in the same types of containers. Though, it demonstrated to be ineffective in the field. Repetitive release of Toxorhynchites first instar larvae in drenched places among bamboo trees had no outcome on mosquito populaces in Indonesia (Annis et al. 1989-1990)

Habitat Elimination:

Mosquito elimination and management practices mostly focused on chemical involvements like residual sprayings and insecticide-treated nets, and these methods still exist in several countries. However, all these options are not considered good for living organisms’ health as well as for the environment. A very suitable and applicable non-chemical mosquito control program using source management has been evaluated and tested in many experimental projects. Source reduction mainly concerns with prevention of the development of mosquito larvae by eliminating their breeding sites mostly including tactics such as drainage, filling, drains, and drainage of irrigation courses. After recognizing primary breeding sites accountable for disease transmission, it is quick to start a selective larval control action, which has been called species sanitation. Housing circumstances might be enhanced, and water supply and sanitation services can also be taken as the main step to launching source management. Many breeding sites can be recognized along nearby banks of the river, seas, or other water-containing bodies for alteration and vegetation removal. Environmental management approaches might prove to be workable over the long term allowing the development of the state by successfully suppressing diseases. Inclusive and integrated mosquito management schemes with the use of adulticides or larvicides, source management, zoo prophylaxis, aerial space spraying, and using coils, screens, and repellents are mandatory. During epidemics, indoor and outdoor residual sprayings are normally applied, usually using insecticides against adults and larvae. This recommends, stimulates, and announces to citizens to decrease mosquito-borne diseases through environmentally helpful approaches that demand no cost expenditure. Pest-borne disease control relies upon source management may be non-toxic, achievable, and cost-effective, and determines the viability of sustainable bioenvironmental vector control. 

An explained report was presented by stressing upon the community outreach program and getting familiar of the public from arboborne diseases. It describes that the education process must start before the onset of community health threats. It also encourages national organizations to begin and sustain credibility and community trust by giving timely, exact, and actionable data about what is known and what is not known. Increased accessibility and information of accurate data about arboviral diseases among populaces and the public onset of risk and delivering suitable action messages for each audience is very essential. Advanced information of and backing for vector control actions should be provided in communities. Increase the volume of health care stations and to share exact health info about arboviral disease prevention should be conveyed to at-risk populations (e.g., pregnant women and women of reproductive age and populations affected by Zika virus). Inspiring actions by community leaders and organizations should be done to guard at-risk populations from arboviral diseases.

Lawler and Lanzaro described that mosquitoes put a risk to livestock and pets. Animals distressed by mosquitoes did not feed and forage well. After being bitten by mosquitoes, cows reduced the milk yield, and other cattle loss their weight. So, it was very important to get rid of mosquitos and maintain the health of livestock at the farm level. The basic principles found very efficient to minimize the increasing populations at the farm level are to discard and avoid stagnant wastewater remains for longer than four days. Weeds should be removed around ditches, ponds and other shallow wetlands. Dried off surface water within four days through proper irrigation. Biological and chemical control of mosquitoes can enhance these important preventive procedures.

Up to date, in the United States, both urban and rural areas are lacking of active mosquito control programs. Mosquitoes often drove humans and animals indoors or into adjoining rivers to escape the masses of blood-sucking mosquitoes. Primary mosquito control approaches involved source reduction, mosquito-eating fish, and chemicals. These practices remain today, in a much more cultured way, but acting upon the rule and laws first implemented by early 20th-century medical entomologists such as L. O. Howard.