Breastfeeding Around the World: Maternal Infections

The infection that is of main concern is HIV, the virus that causes AIDS. HIV is transmitted through breast milk ( WHO, 2007 ). Nduati randomized HIV positive East African women into breastfeeding and formula feeding groups and found increased HIV transmission rates in the breastfed infants compared to those fed formula ( Nduati, 2000 ). A meta-analysis of 4085 breastfed infants who were born to HIV infected mothers in Africa, showed that 993 infants (24%) were infected by the end of the studies. Of the 993 infected infants, 122 (12%) were infected at birth, 225 (23%) were infected by 1 month of age, 223 (22%) were definitely infected after 1 month of age, and 454 (46%) were infected at unknown time ( BF and HIV, 2004 .

"Infant feeding in the context of HIV is complex because of the major influence that feeding practices exert on child survival. The dilemma is to balance the risk of infants acquiring HIV through breast milk with the higher risk of death from causes other than HIV, in particular malnutrition and serious illnesses such as diarrhea, among non-breastfed infants." ( WHO, 2010-1 ). This is most important in the developing world. Consequently the recommendations for feeding infants born to HIV infected mothers will vary depending on where the mother and infant live. In the United States and the developed world, women who are HIV positive are encouraged not to breastfeed their infants ( AAP Breastfeeding, 2005 ) due to the small risk of HIV transmission from the mother to the infant even with maternal and infant HIV treatment.

1. The WHO recommends:
   1. HIV testing and counseling for all pregnant women,
   2. lifelong antiretroviral treatment for HIV-infected women in need of treatment for their own health which is also safe and effective in reducing maternal to child transmission, and
   3. antiretroviral prophylaxis to prevent maternal to child transmission during pregnancy, delivery, and breastfeeding for HIV-infected women who do not meet treatment guidelines for themselves as the most effective strategy in supporting the health of women and their infants ( WHO, 2010-2 ).

2. The WHO policy on infant feeding for mothers who are HIV negative or who don't know their HIV status is, "Exclusive breastfeeding for the first six months of life, with adequate and safe complementary feeding from age six months and continued breastfeeding for up to two years and beyond." ( WHO, 2010-1 ).

3. When children are born to mothers who are HIV positive, the WHO recommends:
   1. Mothers who are infected with HIV and have infants who are not HIV infected or have unknown HIV status should:
      1. exclusively breastfeed their infant for the first 6 months of life,
      2. introduce appropriate complementary foods thereafter,
      3. continue breastfeeding for the first 12 months of life, and
      4. should stop breastfeeding only when there is a nutritionally adequate and safe diet without breast milk ( WHO, 2010-1 ).

   2. When both the mother and infant are known to be infected with HIV, the mother should exclusively breastfeed for the first six months of life and continue breastfeeding as per the recommendations for the general population, that is up to two years or beyond ( WHO, 2010-1 ).

4. The risk of transmitting HIV through breast milk seems to be greater for:
   1. mothers who become acutely affected with HIV during the time they are breastfeeding, in distinction to mothers who were HIV positive during pregnancy ( Van de Perre, 1991 ; Hira, 1990 ),

   2. Mothers who give mixed breast milk and other foods or milks instead of exclusive breastfeeding in the first six months of life.

      In South Africa, Coovadia and Coutsoudis encouraged exclusive breastfeeding for 6 months in a cohort of HIV infected mothers who received nevirapine at the birth of their infant. Median duration of exclusive breastfeeding was 159 days (5 months). Breastfed infants who received solid foods along with breastfeeding were more likely to be infected with HIV at 6 months (Hazard Ratio of 10.87) than infants exclusively breastfed. Cumulative mortality at 3 months of age was 6.1% in exclusively breastfed infants compared to 15.1% in infants given formula (Hazard Ratio 2.06) ( Coovadia, 2007 ). Prior work in South Africa showed that continued breastfeeding longer than 6 months of age with the addition of complementary foods was associated with continued transmission of HIV to the infants.( Coutsoudis, 2001 ).

   3. Mothers with a large amount of HIV virus in their breast milk or blood, or mothers with advanced HIV disease that is manifested by immune deficiency ( WHO, 2007 , Rousseau, 2003 , Manigart, 2004 ).

   4. Maternal mastitis, breast abscesses or nipple lesions ( WHO, 2007 ).

5. Decreased maternal transmission of HIV to the breastfed infant has been associated with higher amounts of the following substances in the breast milk:
   1. antiviral substances such as lactoferrin,

   2. HIV specific killer T lymphocytes,

   3. HIV specific secretory IgA and HIV specific IgM and IgG. ( WHO, 2007 ).

6. Results from trials in Kenya, Malawi, Uganda, and Botswana of exclusive breastfeeding in the infant of the HIV infected mother with rapid weaning at 3-6 months of age have shown increased incidence of severe gastroenteritis and mortality from gastroenteritis within the first 3 months after early weaning from breastfeeding. Although the rate of HIV infection in the infants was less when they were rapidly weaned from breastfeeding at around 6 months of age, by 1-2 years of age the mortality rate and rate of HIV free survival in the group with early weaning was equal to that of the group that continued breastfeeding. This was due to the increased rate of severe gastroenteritis and subsequent mortality in HIV uninfected children. In the study in Botswana, discontinuation of breastfeeding was the strongest predictor of infant illness. Levels of immunoglobulins in maternal breast milk against common bacteria that cause infant infections were no different between mothers infected with HIV and uninfected mothers ( WHO, 2006-1 , Kafulafula, 2010 , Kuhn, 2008 , Kuhn, 2010 , Shapiro, 2007 ).

7. Trials of 4-6 months of prophylaxis with antiretroviral medications in the breastfed infant of an HIV positive mother in Subsarahan Africa with continued breastfeeding have shown significant reductions in infant HIV infection and death ( Thior, 2006 , Kumwenda, 2008 ). Treating the HIV infected mothers during pregnancy and during the first 6 months of breastfeeding with effective antiretroviral medications has also been shown to decrease HIV transmission and infant mortality by 1 year of age. This method may also improve the mother's health. All of these studies included weaning from breastfeeding at 6-7 months of age ( Guiliano, 2007 , Marazzi, 2009 , Palombi, 2007 , Peltier, 2009 ). Further research is underway to determine the optimal duration of maternal HIV treatment during breastfeeding.

An infant whose mother has acute infectious tuberculosis can be infected through close contact. This can happen whether or not the baby is breastfed. In the developed world, these women should be started on appropriate medications, and the infant should be started on Isoniazid. These mothers and babies should be separated until they are both on therapy and the mother is not infectious. These mothers should be encouraged to express their breast milk to build and maintain their milk supply so that they can breastfeed their baby when they are no longer infectious. The expressed breast milk can be fed to the baby ( Lawrence, 2011 pg. 421-425).

In developing countries, if the mother is diagnosed with active tuberculosis within 2 months before delivery, after delivery or has a positive sputum test for tuberculosis, the mother should be treated. The infant can breastfeed and remain with the mother while the infant receives Isoniazid for 6 months. After the infant completes the Isoniazid treatment, the infant should receive BCG ( WHO, 1998 ).