Fighting Zika – the role of long-lasting insecticidal nets as a preventative tool

The World Health Organization (WHO) declared in February 2016 that the Zika virus poses an international public health emergency of international concern, prompted by increasing worries that it is linked to birth defects. As the outbreak grows throughout Latin America and the Caribbean, governments and agencies are rushing to contain this disease.

The WHO has identified long-lasting insecticidal nets (LLINs) as a tool in the fight against Zika. As one of the world’s leading manufacturers of LLINs, TANA Netting has committed to using its vector control expertise as part of the ongoing response to the health emergency. We are currently responding to requests from six different Latin American countries, and are working with partners across the continent to ensure the smooth distribution of the required LLIN products wherever they may be needed.

Millions of people may now have been infected

The Zika virus is a mosquito-transmitted infection that is spread through the bite of an infected Aedes mosquito. The virus was first discovered in 1947 in the Zika forest in Uganda and in the following years cases were commonly reported in tropical Africa, Southeast Asia, and the Pacific.

It began spreading further afield in May 2015, when an outbreak occurred in Brazil. Few people in the Western Hemisphere have immunity against the virus, so it spread quickly, and as many as four million people in the tropical regions of the Americas could be infected by the end of 2016.

Zika virus not the whole story

Whilst the Zika virus has dominated the headlines over the past few months, the Aedes mosquito has long been responsible for the transmission of other vector-borne diseases, such as dengue fever, chikungunya, filariasis and yellow fever, causing many more deaths each year. In 2015, 1.5 million cases of dengue were reported in Brazil alone, and globally an estimated 500,000 people require hospitalisation each year, a large proportion of whom are children. About 2.5% of those affected die.

Whilst Zika is less common than these other diseases, the recent outbreak has raised awareness of the public health problem posed by Aedes and has prompted new efforts to tackle this vector.

Slowing down the spread of Zika and the role of LLINs

Protection against mosquito bites is one of the best forms of prevention, and TANA Netting is at the forefront of efforts to introduce long-lasting insecticidal nets to the newly affected areas. We are in discussions with partners in Panama, Brazil, Ecuador, the Dominican Republic, Nicaragua and Colombia, and our DawaPlus 2.0 deltamethrin-coated polyester netting has been specifically recommended by the World Health Organization as a preventative tool.

The behaviour of the Aedes mosquito differs markedly from the malaria carrying Anopheles mosquito as it bites primarily during daylight hours. For this reason we recommend using full household screening, whereby all household openings are covered with insecticide treated barriers such as our DawaPlus® 2.0 Curtain. This intervention tool needs to be adapted to local contexts, and local implementing partners are vital. Bed nets are also invaluable for those sleeping during the day such as pregnant women, infants, the bedridden and/or elderly, and night-shift workers.

With the Aedes mosquito biting during the day, and both indoors and outdoors, other vector control tools are vital. WHO supports health authorities to implement vector control strategies such as larviciding and larval source management. Public education campaigns have a major role to play as the Aedes mosquito prefers to lay eggs in artificial water containers, people are advised to dispose of items that could collect water or carefully cover or drain them. WHO is also prioritising research, enhancing surveillance, and providing training on clinical management, diagnosis and vector control.

No treatment is currently available

The most common symptoms of Zika are fever, rash, joint pain, and conjunctivitis. The illness is usually mild with symptoms lasting for several days to a week after being bitten by an infected mosquito. People usually don’t get sick enough to go to the hospital, and they very rarely die. For most, the infection causes no symptoms and leads to no lasting harm, with many people not even realising that they have been infected. There is no specific treatment or vaccine available.

 

Potential complications of Zika

During the Brazilian outbreak, potential neurological and auto-immune complications of Zika virus disease were reported. Local health authorities observed an increase in babies born with microcephaly which coincided with Zika virus infections in the general public. Normally, microcephaly occurs in about 1 in 5,000 to 1 in 10,000 of all births, but scientists analysing Zika outbreaks in Brazil estimate that the incidence rose to nearly 1 in 100 births.

Studies to prove whether the virus was to blame are ongoing, but evidence is mounting. The virus is now considered “guilty until proven innocent.” Officials at the Centers for Disease Control and Prevention have advised pregnant women against travel to 30 countries in the Caribbean and Latin America.

Winning the war

Here at TANA Netting we are ready to respond to this public health emergency. Our family-run factory in Lahore, Pakistan, has an annual capacity of more than 50 million long-lasting insecticidal nets. By working hand-in-hand with governments and NGOs we are committed to do whatever it takes to win the fight against Zika.