The New York City Department of Health will spray pesticide from trucks in parts of Queens, the Bronx, and Staten Island between 10 p.m. Thursday and 6 a.m. Friday to reduce mosquito activity and the risk of the Zika and West Nile viruses.

In case of bad weather, the application will be delayed until Monday.

The spraying schedule can be found on the health department’s website or the @nychealthy account on Twitter.

The Staten Island and Bronx neighborhoods are being sprayed with “adulticide” because a large number of Asian Tiger mosquitos have been discovered there.

While a cousin mosquito (Aedes Aegypti) is responsible for the current outbreak in Latin and Central America, the Tiger mosquitos are potential carriers.

No Zika virus or case of Zika transmission from local mosquitoes has been found in the city, but “we are taking no chances,” Health Commissioner Dr. Mary T. Bassett said in a statement.

Other neighborhoods in Staten Island and Queens will be sprayed because they are the sites of increased “West Nile virus activity” and high numbers of bugs from the “Culex family,” that are not known to transmit Zika, but have passed on West Nile in NYC since 1999.

In related mosquito news, Attorney General Eric T. Schneiderman has issued “cease and desist” letters to seven companies that he says are falsely claiming their products prevent or protect against Zika.

Ultrasonic devices and products impregnated with botanical oils are or Vitamin B-based repellents, are ineffective he said. The only effective products, Bassett noted in a statement, contain “DEET, picaridin, oil of lemon eucalyptus and an insect repellent called IR3535.”