The Pan American Health Organization/World Health Organization (PAHO/WHO) is urging member countries that have mosquitoes that transmit dengue and chikungunya to step up their vector-control efforts and prepare for a possible increase in patients suffering from these diseases.

Aedes aegypti/CDC
Aedes aegypti/CDC

The recommendations come as the peak transmission season for dengue approaches and following local transmission of chikungunya in a number countries in Latin America and the Caribbean.

Since the beginning of this year, countries in the Americas have reported nearly 850,000 cases of dengue and 470 deaths from severe dengue. Between December 2013 and 5 September 2014, 650,000 cases of chikungunya, including 37 deaths, were reported in the region.

Both dengue and chikungunya are transmitted by Aedes Aegypti mosquitoes, which are present in the vast majority of countries of the Americas. Canada, Chile (continental) and Uruguay are the region’s only countries that have not reported cases of dengue. Chikungunya cases resulting from local transmission have been confirmed in a number of countries and territories of the Caribbean and more recently in other countries of the hemisphere.

“We are approaching the season when there is more transmission of dengue, and we also face the risk that chikungunya will reach other countries of the Americas,” said Luis Gerardo Castellanos, chief of PAHO/WHO’s Neglected, Tropical and Vector-Borne Diseases unit. “That’s why we need the countries to integrate their efforts to prevent and control both diseases.”

PAHO/WHO is calling on countries to strengthen existing dengue prevention and control strategies and apply them to chikungunya as well. PAHO/WHO recommends stepped-up efforts in six areas: patient care, social communication, epidemiological surveillance, laboratory-based diagnostic capacity, integrated vector (mosquito) control, and the environment.

For mosquito control, PAHO/WHO recommends information campaigns to educate the public on how to eliminate mosquito breeding sites in homes, efforts to eliminate breeding sites from communal areas (such as parks, schools, and cemeteries), and spraying in areas where it is deemed necessary.

“All sectors of government, communities and families need to work together to fight this vector, which tends to live in our homes,” said José Luis San Martín, PAHO/WHO regional advisor on dengue. “The fewer mosquitoes we have circulating, the fewer people will be at risk of bites and of contracting these diseases.”

PAHO/WHO also recommends that countries organize their health services to ensure rapid referral of patients with symptoms of severe dengue, which requires specialized medical care. Health services also need to be prepared to scale up should cases of either disease begin to increase.

Symptoms of dengue include high fever, headache and muscle pain. Severe forms of dengue can cause difficulties in breathing, hemorrhage and even death if patients do not receive early and appropriate treatment. Chikungunya causes high fever initially, accompanied by joint pain. Severe complications are uncommon, but older adults with chronic diseases, children and pregnant women are at risk of more serious illness. There is currently no vaccine for either disease.