Published Date: 2006-06-05 00:00:00
Subject: PRO> Malaria - Europe ex Thailand (02): comment
Archive Number: 20060605.1568
MALARIA - EUROPE EX THAILAND (02): COMMENT
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: Sun 4 Jun 2006
From: Benjamin Cowie <Benjamin.Cowie@mh.org.au>
Malaria - Germany ex Thailand - comment
As most of the areas mentioned that this traveler had visited were
coastal areas in the south near Phuket (Khaolak, Bangsak) and Koh
Samui (Koh Phangan), it would not be unreasonable (and consistent
with CDC and WHO guidelines) for a traveler not to take anti-malarial
prophylaxis if her travel was restricted to coastal areas, although
clearly, a trip of 6 months increases the likelihood of unforeseen
and possibly extensive changes to travel plans with attendant
difficulties in offering comprehensive prospective medical advice.
However, Ranong is the least populated Thai province, is mountainous,
and in parts heavily forested, having the highest annual rainfall in
Thailand. Given these factors, it is unsurprising that Ranong is
malaria endemic (1). As pointed out by the moderator, being a border
area with Myanmar, mefloquine resistance is a concern and should not
be used for prophylaxis against malaria in travelers to these
regions. Doxycycline is an alternative to atovaquone-proguanil.
Thailand exemplifies the potential hazards of prescribing
anti-malarial prophylaxis simply by country. There is no risk in
Bangkok and major tourist areas such as Koh Samui and Phuket, as
reflected in the CDC and WHO guidelines, but hilly, forested regions
near international borders are endemic. A travel specialist should
therefore not recommend anti-malarial prophylaxis for all travelers
to Thailand, but should assess whether the traveler will enter
malarious areas of Thailand and advise accordingly.
The tragic outcome in the case mentioned was of course contributed to
by the failure to seek medical advice despite days of febrile
illness. Any fever occurring while in or after return from a
malarious area must be assumed to be due to malaria until formally
excluded, irrespective of any prophylaxis taken (2). It is not
mentioned whether this traveler sought pre-travel advice or what
other preventive measures were taken, but the missed opportunities to
avert this death are reminders of the importance of a comprehensive
pre-travel consultation, particularly for extended travel.
(1) Chaijaroenkul W, Bangchang KN, Mungthin M, Ward SA. In vitro
antimalarial drug susceptibility in Thai border areas from 1998-2003.
Malar J. 2005 Aug 2;4:37.
(2) Yung A, Ruff T, Torresi J, Leder K, O'Brien D. Manual of Travel
Medicine: A pre-travel guide for health care practitioners. 2nd
Edition. Ch. 3: Malaria Prevention. IP Communications, Melbourne 2004.
Dr. Benjamin C. Cowie MBBS Grad.Dip.Clin.Epi. FRACP
Infectious Diseases Physician
Victorian Infectious Diseases Reference Laboratory
10 Wreckyn Street, North Melbourne
Victoria 3051, Australia
[ProMED thanks Dr. Cowie for his comment. Malaria prophylaxis is a
difficult subject regarding countries with uneven risk, and travelers
off the beaten track should consult a travel medicine specialist.
There is an ongoing discussion in Europe about whether or not to
recommend malaria prophylaxis to any traveler to southeast Asia but
instead to provide standby emergency treatment and advice on the use
of impregnated bed nets and repellents. The reason for this
discussion is an awareness of potential side effects from the drugs
used for prophylaxis, which must be balanced against the risk of
malaria. Better knowledge of the distribution of malaria in countries
with variable malaria transmission in different areas is clearly
needed. - Mod.EP]