There was a 51.6 percent increase in the number of dengue cases from the period covering January 1 to March 27, 2010 compared to the same period last year, according to data released by the National Epidemiology Center (NEC).

The NEC said reports from affiliated hospitals nationwide pegged the total number of dengue cases at 11,871 with 77 deaths during the first three months of the year.

The bulk of the cases came from the National Capital Region, Central Visayas, Eastern Visayas, the CALABARZON (Cavite, Laguna, Batangas, Rizal, Quezon), Zamboanga, and Western Visayas.

Clustering of dengue cases was noted in Caloocan, Valenzuela, San Fernando City in La Union, Jaen, Nueva, Rodriguez, Antipolo City in Rizal; Mogpog, Marinduque; Naga City, Camarines Sur; Roxas City, Capiz; Passi City, Iloilo and Bacolod City, Negros Occidental, among others.

The ages of those infected by dengue ranged from one to 90 years old, with 52 percent of the cases male.

Earlier, Health Secretary Esperanza I. Cabral warned that dengue is present all-year round and the public should not be complacent. Health officials also warned that the public should be careful with the use of water containers as this is a potential breeding ground for mosquitoes.

In the hot summer season, people tend to aggressively collect water and store them in containers which when not covered properly help become a breeding ground for mosquitoes, said Dr. Lyndon Lee Suy, DoH expert on emerging and re-emerging infectious diseases, in a previous interview.