Human myiasis in western Jamaica: five years after the implementation of a screwworm eradication programme

To determine the distribution of cases of human myiasis admitted to the Cornwall Regional Hospital (CRH), Jamaica, between 1999 and 2003, following the inception of the National Screwworm Eradication Programme (NSEP) in 1998, and the risk factors associated with the condition.

A total of 144 cases of myiasis were retrieved from the database of the department of Medical Records at the CRH for the years 1999 to 2003. A data extraction form was devised to review the circumstances of each case. The data were analyzed using EpiInfo version 6.

Of 144 cases, 54.9% were female and 45.1% male. The largest groups were < 10 years, 52.8% [76/144 (M-21, F-55)] and 60years and over, 18.8% [27/144 (M-16, F-I)] (p < 0.001). Case distribution for the years 1999-2003 showed 16, 39, 31, 30, and 28 cases respectively. Three-quarters (74.6%) of all cases affected the scalp/head one-fifth (20.3%) affected the lower limbs. Ninety-six per cent of those < 10 years had scalp/head myiasis (p < 0.001; OR = 23.29; CI: 6.14 < OR < 104.11). Two-thirds (66.6%) of those 60 years and over had lower limb myiasis (p < 0.001; OR = 19.09; CI: 6.20 < OR < 61.12). Mean duration of treatment was 3.5 days (SD = 1.4 days) and 69.7% required hospitalization for seven or more days. There was no difference in duration of treatment for myiasis or in length of hospitalization in relation to method used to eliminate maggots. Risk factors identified included Tinea capitis for myiasis of the scalp/head (p < 0.001) and diabetes mellitus for lower limb myiasis (p < 0.001; OR = 14.48; CI: 2.37 < OR < 133.25).

Human myiasis remains a public health issue in western Jamaica with no significant decreasing trend in the number of cases admitted to the CRH since 1999. It is recommended that this zoonosis become a Class 1 notifiable disease to the Ministries of Health and Agriculture because of the existing NSEP.