APHIS is the regulatory agency within the U.S. Department of Agriculture (USDA) tasked with the mission of mitigating/eliminating the impact of foreign and domestic pests on US agricultural production.  APHIS is directed primarily on preventing exotic, non-indigenous pests from entering and establishing themselves within the US.  Implementation of a preclearance program is one way to achieve this goal.

Preclearance is a strategy designed to eliminate the threat of introducing pests to the US prior to departure of export shipments from the country of origin.  In Haiti, this activity focuses exclusively on the preclearance of mango shipments bound for the US.

Production and exportation of mangos provides a significant source of income for approximately 150,000 Haitians, most of whom live in rural areas.  The broad impact on the Haitian population and economy is attributable to a unique characteristic of mango production in the country that differentiates it from elsewhere.  It’s a cottage industry because Haiti lacks a network of mango orchards.  Most exported mangos are harvested from backyard trees.

The major pest complex impacting the mango industry of Haiti is fruit flies.  These are not the familiar tiny flies associated with fermenting fruit, which are more accurately referred to as fermentation or vinegar flies.  The fruit fly pests of mangos belong to an entirely different insect group.  Individuals are about the size of the common house fly, and attack fruit before it ripens.  Preventing the introduction of these pests into the US ranks as one of the highest priorities of APHIS.

The APHIS-approved method of choice for controlling fruit fly infestations in mangos is hot water treatment (HWT).  Upon arrival at the export plant, slightly immature fruit is sorted, screened for evidence of fruit fly infestation, and then dipped in a hot water bath (115ºF) for 60-90 minutes depending on size.  The objective is to raise the core temperature of each individual piece of fruit to 113ºF.  This temperature is lethal to fruit fly larvae, but does not damage the fruit.

During the 2011 season, ten packing facilities equipped with APHIS-approved HWT systems operated in Haiti—nine in Port-au-Prince and one in Pont Sonde, and more than 20 million pounds of mangos were certified for shipment to the US.  The Haiti Mango Preclearance Program is not a US foreign assistance effort.  The entire cost of the program is borne by the local export association.