Introduction:

Mexico City has no endemic presence of Aedes aegypti, and it is therefore free of vector-borne diseases, such as dengue fever, Zika and chikungunya. However, evidence has shown the presence of Aedes aegypti eggs in the city since 2015.

Objective:

To report the constant and increasing presence of Aedes aegypti eggs in Mexico City from 2015 to 2018.

Methods:

Surveillance was carried out using ovitraps. Eggs were counted and hatched in order to determine the species.

Results:

From 2015 to 2018, 378 organisms were identified as Ae. aegypti. In total, 76 Aedes aegypti-positive ovitraps were collected at 50 different places in 11 boroughs of the city. Northeastern Mexico City was the area with the highest number of positive traps.

Conclusions:

The results may be indicating a period of early colonization and the probable existence of cryptic colonies of the mosquito, and Mexico City could be therefore at risk of experiencing vector-borne epidemics.