Number of Zika virus cases in Jaipur has risen and it has the risk of spreading to other areas.
How does the outbreak evolve?
Zika virus was first identified in Uganda in 1947 and the outbreaks of Zika virus have been recorded in Africa, the Americas, Asia and the Pacific.
The disease has been reported from across 86 countries.
The carrier of this virus is the same day-biting Aedes aegypti mosquito that spreads dengue, chikungunya, and other vector-transmitted diseases and is present in hordes in most parts of the country.
There is no available drug or vaccine against Zika, while the treatment is mainly supportive.
Hence, Vector control is the key to prevention and control of Zika virus infection.
The first outbreak in India was reported in Ahmedabad in January-February 2017.
The second outbreak was reported after five months in the Krishnagiri district of Tamil Nadu.
Both were successfully contained through intensive surveillance and vector management.
This is already the third episode of zika eruption in India in less than two years.
Thus the disease continues to be on surveillance radars of the Union health ministry, although it is no longer a public health emergency of international concern, according to WHO.
What are the threats?
Unlike in the past when the virus was detected in infected patients only, this time the scientists have been able to trace it even in the mosquitoes, indicating the danger of its dispersal.
Though Aedes mosquitoes normally do not move beyond 400 to 500 metres, the same is not true of the zika-infected human beings.
They can serve as zika carriers even during the virus’ incubation period prior to the appearance of the symptoms.
So, treating the Jaipur zika outbreak as an isolated case and limiting the control measures to that region alone would be imprudent.
Deaths due of the zika virus are rare and the patients typically recover in two to seven days.
Most symptoms of zika virus are the same as those of dengue and other types of viral flu such as high fever, headache, muscle and joint pain, skin rashes and conjunctivitis-like eye troubles.
But this virus is dreaded more than other vector-borne infections because of its effects on pregnant women.
It strikes directly at the foetus and deforming the brain of the unborn child, resulting in the birth of children with mental and physical disabilities.
It can also cause miscarriage or premature delivery, with some adult patients can also face neurological complications.
Also, recently scientists examining patients with Guillain–Barre syndrome (GBS) in south India have found the presence of antibodies against Zika virus (ZIKV).
This indicates the possibility that the patients who got infected from the ZIKV virus also contributed to the GBS disease.
What should be done?
Control - In the absence of any vaccine or specific drugs to cure zika, protection from mosquito bite and mosquito control are the only ways to combat this menace.
This requires breaking the breeding cycle of the mosquitoes by destroying their eggs and larvae rather than just killing the adult mosquitoes as is usually done through fogging.
Prevention - A nationwide mosquito control programme of the kind that had, in the past, helped in nearly eradicating malaria is needed once again.
The option of using the highly effective pesticide DDT is no longer available on account of an ill-advised ban on it.
Hence, alternate measures such as larvae-eating fish and mosquito predators would need to be deployed to check mosquito multiplication.
Implementation – The National Vector-Borne Diseases Control Programme has not been implemented properly and it is resurrected only during disease epidemics.
If it is implemented on a regular basis on the lines of the polio control programme, it can help avert zika and also scourges such as malaria and Japanese encephalitis.
However, Aedes mosquitoes breed even in small collections of fresh water in and around homes, schools and work sites.
Hence door-to-door surveys to monitor the presence of larvae and suitable action against the defaulters are absolutely essential.
The government should realise that the gains from spending resources on taming disease-dispensing vectors would far outweigh the cost of dealing with recurrent disease outbreaks and take measures accordingly.