chikungunya fever

The city of Nanjing, capital of East China's Jiangsu Province on Monday called for all citizens to raise awareness about mosquito and insect prevention, avoid mosquito bites and improve hygiene and sanitation to mitigate the risks of mosquito-borne diseases such as dengue fever and Chikungunya fever, according to an official notice released by the Nanjing Municipal Center for Disease Control and Prevention (Nanjing CDC).   

The notice was issued against the backdrop of local transmission of Chikungunya fever in South China's Guangdong Province. The number of new locally transmitted Chikungunya fever cases declined in Guangdong over the past week, though risks remain, local disease control authorities said on Sunday. 

A total of 2,892 local infections were reported from July 27 to August 2, with no severe or fatal cases recorded, the Xinhua News Agency reported. 

As of now, no cases of Chikungunya fever have been reported in Nanjing.

"Summer is the peak season for mosquito-borne infectious diseases. Currently, our city is experiencing high temperatures and frequent rainfall, which have led to active mosquito breeding and an increased risk of disease transmission," the Nanjing CDC said. 

Specifically, the Nanjing CDC outlined four key measures for disease prevention and control, including enhancing mosquito prevention awareness, cleaning the environment, paying attention to personal protection and conducting regular health monitoring.

The local health authority recommends that residents learn and understand the transmission and dangers of mosquito-borne diseases, recognize symptoms of common mosquito-related illnesses, and strengthen personal protection awareness. Special emphasis is placed on elderly individuals, children, and pregnant women to heighten their protective measures.

Households are advised to carry out thorough cleanings every 5-7 days, covering areas such as courtyards, balconies, rooftops, storage rooms, stairwells, kitchens and bathrooms. Measures also involve promptly disposing of household waste, empty and clean containers to prevent hidden water accumulation, and maintain a dry and clean environment.

Communities and institutions are advised to designate specific times each week for focused environmental sanitation efforts. These efforts should focus on clearing public areas and outdoor workplace environments of garbage, debris and construction waste to reduce mosquito breeding sites. Remove or invert idle containers that can collect water, and inspect and clean roof drainage systems and rainwater wells to ensure proper flow, it said.

According to the Nanjing CDC, residents are also encouraged to install screen windows to block mosquitoes. When mosquitoes are found indoors, people are advised to use insect repellents such as aerosol sprays, mosquito coils (traditional or electric), or electric mosquito swatters to eliminate them.

When engaging in outdoor activities, the Nanjing CDC suggests that people wear light-colored long-sleeved clothing and pants. Avoid mosquito-prone areas such as shaded spots, grassy areas, or watersides during peak mosquito activity times, such as early morning or evening.

In terms of travel health advisory, the CDC advises people to check health advisories and warnings for their destinations to understand areas experiencing outbreaks or high risks of diseases like Chikungunya. Upon returning to Nanjing, if symptoms such as fever or rash appear, residents should go to hospital for treatment immediately and inform doctor of travel history.

After returning from the affected areas, individuals are advised to monitor their health for about 2 weeks. If any suspected symptoms such as fever or rash occur, people should seek medical attention promptly, said local media outlet Xinhua Daily.

It added that all provincial, municipal, and county-level disease control centers in Jiangsu are capable of detecting the Chikungunya virus, which can be rapidly confirmed through nucleic acid testing.

Tao Lina, a Shanghai-based medical observer, told the Global Times on Monday that Chikungunya is a viral disease primarily transmitted through Aedes mosquito bites, with an incubation period of 3-7 days and a total disease course of 1-2 weeks. The viremic phase, during which the virus is present in the blood, typically lasts 1-5 days.

Mosquitos acquire the virus by biting infected humans or non-human primates (such as monkeys or orangutans) and can then transmit it to healthy individuals through subsequent bites, Tao said. 

Considering the relatively short lifespan of mosquitoes and the low density of Aedes mosquitoes in the Yangtze River Delta region, the efficiency of disease transmission is limited when proper isolation measures are implemented, Tao noted.