Analysis on Imported Malaria Cases in Central Taiwan during, 2006-2010

Min- Tsung Lin1, Sung-Hsi Wei1, Ming-Chu Kuo2, Du-Ling Lin1, Chih-Tsung Tu1, Horng-Ying Chiou3, Tsuey-Feng Lee4

2011 Vol.27 NO.23

Correspondence Author: Min- Tsung Lin


Certification of recognizing Taiwan as a malaria eradication area was issued by the World Health Organization in 1965. From then on, Taiwan entered the stage of prevention of reintroduction in malaria control, and, since then, most of the cases identified in Taiwan were imported, with an average of 30 reported cases per year. This study reviews the records of the epidemiological investigation conducted by the Third Branch of Taiwan Centers for Disease Control (Taiwan CDC) on confirmed malaria cases reported from central Taiwan areas during 2006-2010, and analyzes the characteristics of these cases. A total of 90 malaria cases were confirmed nationwide in Taiwan during the five-year period, 20 (22%) of them from the central Taiwan. Of the 20 cases, all were imported, among them, 12 were citizens and 8 were foreigners. The laboratory examination showed 14 cases were infected with P. falciparum, mainly from Africa, and 6 cases were infected with P. vivax, all from Asia. Fifteen of the twenty cases had a travel history to malaria infected areas, and 80% of these cases were either working or doing business there. Although 33.3% of the fifteen cases have used malaria chemoprophylactic drugs, they were still infected because interruption of taking drugs due to side effect, did not follow doctor’s advice to take the drugs completely, and had used drugs not recommended by physician. Thirty percent of the 20 imported cases had visited private clinic for medical attention when they became ill after returned but were not correctly diagnosed by physician at the first time. This indicates that the physicians’ vigilance and ability in malaria diagnosis still needs to be improved. All the drugs for treatment of malaria cases were provided by the Taiwan CDC within 24 hours after being laboratory confirmed. The treatment regimen for P. falciparum cases was artemisinin-based combination therapies (ACTs). For P. vivax cases, primaquine was added to the regimen for preventing relapse, and, for cases in severe condition, an intravenous therapy with artemisinine was used. Based on the results of the characteristic analysis on these cases, we suggest that citizens planning for a trip to malaria endemic areas should consult physician in travel medicine clinic before leaving the country and should take appropriate prevention methods to reduce the risk of malaria infection. In addition, clinical physicians should inquire patients with fever symptoms about their travel history and conduct microscopic examination of the blood smear for patients with travel history to malaria endemic areas since the examination is very helpful in the early diagnosis of malaria.