Incidence of haemolytic disease of the newborn in Harare, Zimbabwe

BACKGROUND

Haemolytic Disease of Newborn is responsible for a number of neonatal deaths and complications worldwide. Its incidence in Zimbabwe is not clearly understood.

OBJECTIVE

To find out incidence of Haemolytic Disease of Newborn in Harare and ability to identify antibodies associated with HDN.

METHODS

A retrospective cross sectional study at the Parirenyatwa Group of Hospitals and National Blood Service, Zimbabwe (NBSZ). We studied 22493 infants at Parirenyatwa Hospital during the 1995-1997 and 2002-2003 periods. The main outcome measures were ABO and Rh blood group results, Direct Antiglobulin Test and Maternal Antibody Screening and Identification Results were obtained from the NBSZ.

RESULTS

One hundred and ninety-one (0.85%) infants had Haemolytic Disease of Newborn. One hundred and sixty-three (85.34%) of these were due to anti-AB, twenty five (13.09%) were due to anti-D and three (1.57%) due to anti-Kell. Incidence of Haemolytic Disease of Newborn during 1995-1997 and 2002-2003, were 0.93% and 0.64%, respectively (p = 0.014). ABO Haemolytic Disease of Newborn showed a statistically significant difference during the two periods (p = 0.003). Rhesus Haemolytic Disease of Newborn showed no statistically significant difference during same periods (p = 0.317).

CONCLUSION

The incidence of Haemolytic Disease of Newborn at Parirenyatwa Hospital is comparable with that found in other countries. It is recommended that K antigen be included in the pretransfusion testing to avoid anti-K related Haemolytic Disease of Newborn.

Demographic and social characteristics of regular donors who sero-converted in Harare

Zimbabwe, like any other country, is currently experiencing a fast growing HIV/AIDS pandemic. A considerable number of infections are caused by blood transfusion. The aim of this study is to determine risk factors, events and socio-demographic characteristics associated with incidence of HIV infections and to prevent sero-conversion of regular blood donor. A retrospective cross sectional study was done. 22,922 regular donors at National Blood Transfusion Services in Harare were used. The number of all regular donors who sero-converted and their status during the 1999 to 2001 period were determined. About 327 (1.4%) of the regular donors sero-converted. Two hundred and seventy-four (84%) were males and 53(16%) were females. 52.6% of the males were married, 46.7% were single and .7% separated. 30.2% of the females were married, single women 67.9% and separated women 1.9%. Increased sero-conversion was associated with unemployment, high-density area residence and the sexually active age group (21 to 45 year olds). There was an association between gender and marital status among sero-converters (c2 = 8.48; P-value = 0.014) and males were likely to be older than females (t = 2.9; P-value = 0.0019). It can be concluded that unemployment and living in high-density residential areas are highly associated with HIV sero-conversion among regular donors. Single females, working class males and the sexually active age group are highly exposed to risk factors. It is recommended that donor education schemes and knowledge of these factors should be considered during donor recruitment.

Prevalence of HIV infection in school based and other young donors during the 2002 and 2003 period

The majority of donor blood in Zimbabwe comes from school-based donors. Zimbabwe has one of the highest HIV prevalences in the world and the age at which the infection is acquired is decreasing. This is a serious threat to the safety of blood supply. The prevalence of HIV has been low among the youth the majority of whom are still going to school and between the ages of sixteen and nineteen years. However, due to the changing socio-economic environment, sexual behavioural patterns have also changed. It is now necessary to evaluate these changes in order to guarantee safe blood transfusion. To determine the prevalence of HIV among adolescent donors during the period between 2002 and 2003. Cross-sectional retrospective study, National Blood Transfusion Service (NBTS). All school based donors and others between 16 and 19 years of age. The number of donors who were HIV positive in this age group. Data on donors was collected from computer files at the National Blood Transfusion Service (NBTS) Information Technology (IT) department. Prevalence of HIV was determined and categorised according to gender, age and the type of school the donor attended. The prevalence of HIV in 2002 and 2003 were 0.48% and 0.38%, respectively. Sixty-six per cent (66%) of HIV positive donors had donated for the first time. The prevalence in both periods was much higher in female donors than male donors. In 2002 males and females had prevalence of 0.28% and 0.66%, respectively. In 2003 males and females had prevalence of 0.18% and 0.55%, respectively. The overall highest prevalence (0.90%) was found between the 16-19 year age group who were not going to school (others). In 2002 female day schools had the highest (0.87%). The lowest prevalence (0%) was found in male boarding schools. In 2003 the highest prevalence (1.61%) was found in the 16-19 year age group who were not going to school (others). The lowest prevalence (0) in the same year was found in male boarding scholars. It can be concluded that the majority of HIV positive school based donors are first time donors. Female scholars and those of the same age group who are not going to school have the highest risk of donating HIV positive blood than male donors. The prevalence of HIV in adolescent blood donors decreased with age. It is recommended that active donor recruitment should be in favour of the low prevalence groups.