Health officials announced this year's second case of West Nile virus in Mississippi, which was discovered in Adams County. The announcement comes about one week after the first case was reported in Hinds County, WTVA reports.

According to Dr. Thomas Dobbs, epidemiologist for the Mississippi State Department of Health, West Nile virus can occur throughout the year, but the number of cases typically increases from the months of July to September.

The state health department cautioned all residents of Mississippi about the potential risk to its residents. It urges tehm to avoid mosquitoes by staying indoors and using protective measures such as insect repellent with up to 30 percent DEET.

Forty-three West Nile virus cases resulting in seven fatalities were reported for Mississippi in 2014, according to the MSDH website.

Meanwhile, other places in the U.S. reported a spike in the number of mosquitoes testing positive for the virus. In Orange County, Calif., 32 mosquito samples tested positive, with 26 of these coming from a particular two-block area inTustin, ABC 7 reports.

Mosquito samples also tested positive for West Nile virus in the city of Santa Clara, prompting authorities to schedule a fogging treatment on July 29. The fogging will cover areas in Tasman Drive and Great America Parkway, all the way to Sunnyvale and San Jose, NBC Bay Area reports.

In Indiana, Marion County reported its first confirmed mosquitoes carrying West Nile virus while Hamilton County identified mosquitoes found in Carmel's Meadowlark Park positive for the virus, WTHR reports.

Health officials are attributing the spike in West Nile virus cases to the drought being experienced in certain areas in the U.S. this year. The drought reportedly causes mosquitoes to look for artificial sources of water, such as standing bodies of water found in residential areas, increasing the possibility for humans to contract the disease, CBS News reports.