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Primary amebic meningoencephalitis caused by Naegleria fowleri, Karachi, Pakistan
Sadia Shakoor1, Mohammad Asim Beg, Syed Faisal Mahmood
1Aga Khan University Hospital, Karachi, Pakistan.
Emerging Infectious Diseases
|February 5, 2011
Abstract:
We report 13 cases of Naegleria fowleri primary amebic meningoencephalitis in persons in Karachi, Pakistan, who had no history of aquatic activities. Infection likely occurred through ablution with tap water. An increase in primary amebic meningoencephalitis cases may be attributed to rising temperatures, reduced levels of chlorine in potable water, or deteriorating water distribution systems.
Insights
Naegleria fowleri infections caused primary amebic meningoencephalitis in Karachi, Pakistan, even without swimming. Tap water used for ablution was the likely source, highlighting a potential public health risk.
Area of Science:
- Infectious Diseases
- Public Health
- Environmental Microbiology
Background:
- Naegleria fowleri is a free-living ameba known to cause primary amebic meningoencephalitis (PAM), a rare and fatal brain infection.
- PAM is typically associated with recreational water activities, such as swimming or diving in warm freshwater.
Observation:
- Thirteen cases of PAM were identified in Karachi, Pakistan.
- None of the affected individuals reported any history of aquatic activities.
- Infection was suspected to have occurred through ablution using tap water.
Findings:
- The study identified a cluster of Naegleria fowleri PAM cases in an urban setting without typical exposure routes.
- Tap water, commonly used for ablution (ritual cleansing), emerged as the probable transmission vehicle.
- The findings suggest a potential shift in the epidemiology of Naegleria fowleri infections.
Implications:
- This highlights the risk of Naegleria fowleri infection through non-aquatic tap water exposure, particularly in regions with specific water usage practices.
- Public health strategies may need to be revised to include tap water safety and hygiene measures.
- Environmental factors like rising temperatures, reduced chlorine levels, and compromised water distribution systems could be contributing to an increased incidence of PAM.
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