MOZZIE MENACE

Hi viewers, thank you for the fantastic response last month. Upcoming articles are more exciting with new information; so click the Follow button on the top-left corner in your screen to get all the notifications of the blog. Well today’s article is a very important topic on which I have researched the most. You may wonder what the article is all about and what the title of the post suggests; Have patience! it’s worth reading.

‘Mozzie/mossie’ is a tern picked from Australian slang which refers to ‘mosquito’. Mosquito menace is never ending, but it cannot be neglected because of their disease transmitting capacities. They are considered as the deadliest insects ever on the earth. May be due to the life threatening diseases it spreads or sleepless nights due to its irritating noise produced by their wings; ultimately, ‘mozzie menace’ is insufferable. Only female mosquitoes suck blood of any animals or human beings because females require more energy for ovary developments and ovipositions (egg laying). Male mosquitoes on the other hand feed on nectars and plant saps like honeybees. Hence only females are involved in transmission of nay diseases.

There are number of diseases which are been transmitted by mosquitoes such as, malaria, dengue, chikungunia, Japanese encephalitis, yellow fever (only in Africa and S. America), filariasis, zika, West Nile fever and many more. Specifically Aedes mosquitoes alone transmit most of the disease like, dengue, chikungunia, yellow fever zika virus and filariasis (islands of Pacific). Unlike the other mosquitoes, ‘Aedes’ bites only during the day-time, particularly 3O’ clock to 4 O’clock. There are two main species of ‘Aedes’ in India which are vectors namely, ‘Aedes aegypti’ and ‘Aedes albopictus’. ‘Aedes’ mosquitoes are comparatively smaller than other mosquitoes.

Description: black/greyish body with white alternative bands on the abdomen and limbs. (It can be easily identified due to its stripped limbs). In case of ‘Aedes aegypti’, thoracic region contains 3 vertical bands, they are also called as domestic mosquitoes since they are closely associated with humans. ‘Aedes albopictus’ (Asian tiger mosquito/forest mosquito) contains one single vertical white band on thoracic region making itself unique from Ae. aegypti. They usually breed in forest regions.

Life history: There are 4 stages in its life cycle; namely, egg, larva, pupa and adult. Egg resemble pencil tip, they are elongated, oval, black in colour and shiny surface. It hatches within two days. Next is larval stage which is the longest stage with 4 instars; they continuously feed on algae and other microscopic planktons. The 4^th instar larvae molt into pupae which molt into adults in 2 days.

It is an interesting fact that the ‘mozzie menace’ can be overcome by understanding their life cycle and taking proper measures accordingly.

I. Controlling mosquitoes in egg stage:

Aedes female after a blood meal lays around 200 eggs in stored water (not sewage water). They usually prefer abandoned tyre, earthen pots, cement tanks, buckets and other stuffs which can hold water for their breeding. Ae. albopictus breeds in tree holes, coconut shells, and other water holding substances in forests. When I was doing my project work, I use to keep some water in the dustbin to attract Aedes to breed. I have sighted eggs in unused bath wares/sanitary wares with little water, disposed buckets and vessels in backyards, drinking water cans, money plant water holder and even in empty jam box with little water stored. Sometimes even in any cup like projections in statues may also attract them.

ü Therefore the first way to control Aedes is to demolish all the breeding places.

ü Keep your surrounding clean; don’t let rain water collect in any vessels.

ü In case if you site Aedes eggs, then,

ý Do not throw it in sink or drain.

ü Instead, discard the water on rock or any dry place where there is no water collected.

ü Aedes eggs can survive up to 2 years without water, so make sure that you have discarded in the right place.

II. Controlling mosquitoes in larval stage:

Larval control is the best among all. Large number of mosquitoes can be killed; it’s easy and convenient method than others. Larvae continuously feed until it pupates, so if we alter the water quality it may not be resistible for them to survive. In case if you sight any larvae, then

ü Discard the water along with the larvae in dry places.

ü Simply squeeze a lemon into it, the alkaloids like limonoids present in the lemon chokes the gut of larva and kills it.

ü I have tried adding a tablespoon of salt to the water, luckily the result was fantastic (100% mortality).

ü There are many plant extracts which are proved as the best larvicidals, I have tried the alcohol extracts of Abutlion leaves, lemon peel, papaya seeds, wonder berry leaves etc.

WHO method Bioassay

ü In case of ponds make sure you are not disturbing any other life forms in such cases,

ü Guppy and Gambusia fish are the boon for us in controlling larvae.

ü Frogs, toads and salamanders also predates on larvae.

III. Controlling mosquitoes in pupal stage:

Controlling mosquitoes in its pupal stage is a bit complicated since they do not feed anything (remains dormant until it becomes an adult), but any methods used to control larvae may also holds good for them as well.

IV. Controlling mosquitoes in adult stage:

Adult mosquitoes can be controlled in various methods; there are varieties of mosquito repellent and killing devices available in the market. When you want to control mosquitoes in large number then follow any of these,

ü Spray DDT, premethrin, malathionetc in your backyard.

ü Cut a lemon into two equal halves, take some cloves and stuck them all inside the lemon pulp; place these near the windows. This acts as a very good mosquito repellent.

ü Crush a bunch of Hyptis suaveolens (bush mint) leaves and apply it on hands and legs. The strong odour of the leaves repel mosquitoes.

ü Mosquitoes are attracted to us because of CO₂in our sweat; if we manage to remove the sweat odour by applying repellent creams it will distract their paths.

ü Aedes usually bites during 3O’clock – 4O’clock in the noon time, so avoiding mosquito bites especially during these timings will save you all.

ü Make sure you use only biological methods and stay eco-friendly

ý Avoid using chemical insecticides, coils, liquid vaporizers since the insects like mosquitoes shows high evolution of resistance towards chemicals.

ý Aedes do not breed in sewage or drainage water, but Culex species do.

Now that you have learnt lots of methods, I bet you will fight against ‘mozzies’ like a boss. There is an advanced way of controlling mosquitoes which is by introducing genetically sterile male flies to mate with normal females; further investigations are required in this field. Although female mozzies are our enemies, males are beneficial for us by helping in pollination. It's survival maintains the ecological balance.

Breeding sites of Aedes: