Is leishmaniasis endemic in this location?

Leishmaniasis Endemicity Assessment

Direct Answer Based on Location

The endemicity of leishmaniasis depends entirely on the specific geographic location in question, but I can provide definitive guidance based on established endemic regions worldwide.

Global Endemic Regions

New World (Americas)

High-Risk Endemic Areas:

• South of the Amazon basin in Bolivia, Peru, and Brazil (the "mucosal belt") represents the highest risk area for mucosal leishmaniasis 1
• Moderate-risk areas extend from south of Nicaragua to the Amazon basin 1
• Low-risk areas include New World endemic regions north of Costa Rica 1

United States Endemic Status:

• Leishmaniasis is definitively endemic in the United States, particularly in Texas and Oklahoma, with 59% of 69 identified cases (2007-2017) occurring in patients with no travel history outside the US within 10 years 2
• Leishmania mexicana was identified in 100% of speciated endemic US cases 2
• The median age at diagnosis for endemic US cases was 61 years, with 68% occurring in females 2

Old World (Africa, Middle East, Asia)

Major Endemic Regions:

• Asia and Africa are most endemic for visceral leishmaniasis, commonly affecting young children 3
• Mediterranean destinations are emerging as main areas of acquisition for European travelers 4
• Sri Lanka has seen rising incidence since 2008, with 90% of cases concentrated in Anuradhapura, Hambantota, Polonnaruwa, Kurunegala, and Matara districts 5

Clinical Implications by Geographic Risk

For Exposures in High-Risk Mucosal Belt (Bolivia, Peru, Brazil south of Amazon)

Treatment is mandatory even for healed lesions because the risk of developing destructive mucosal leishmaniasis is substantial with Viannia species, particularly L. (V.) braziliensis 1

For Exposures North of Costa Rica or Old World

Observation may be reasonable for simple cutaneous leishmaniasis (single small lesion <1 cm, non-cosmetically important location, immunocompetent host, spontaneously healing) because mucosal leishmaniasis risk is low 1

For US-Acquired Cases

Consider endemic acquisition in patients from Texas, Oklahoma, or other southern states even without travel history, as L. mexicana is established in these regions 2

Seasonal and Environmental Factors

Peak transmission periods vary by region:

• North-central Sri Lanka: July to September 5
• Southern Sri Lanka: October to December 5
• Maximum temperature, humidity, and wind speed significantly correlate with transmission in endemic regions 5

Diagnostic Approach for Endemic vs. Travel-Associated Cases

Species identification is critical because it determines treatment strategy and prognosis 1:

• Viannia species from Costa Rica southward require systemic treatment regardless of lesion appearance 1
• Old World species or New World non-Viannia species may be observed if lesions are simple and healing 1

Common Pitfalls

Do not assume leishmaniasis requires international travel - endemic transmission occurs in the southern United States, and climate models predict doubling of exposed US citizens by 2080 2

Do not rely solely on recent travel history - leishmaniasis can manifest months to years after exposure, particularly for mucosal disease 1, 4

Do not dismiss the diagnosis in immunocompromised patients from endemic areas - reactivation of dormant infection can occur with HIV, transplantation, or immunosuppressive medications 1