Prevention of mother-to-child HIV transmission internationally.

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Prevention of Mother-to-Child
HIV Transmission
Internationally1
Data from the Joint United Nations Programme on
HIV/AIDS (UNAIDS) indicate that in 2003, 34–46 million
people were living with HIV infection, and three fourths of
these cases were in sub-Saharan Africa. Approximately
2.1–2.9 million children were living with HIV/AIDS. HIV
transmission in sub-Saharan Africa is predominately het-
erosexual, and by the end of 2002, women represented 58%
of HIV cases. UNAIDS estimates that in many African
countries <1% of pregnant women receive needed anti-
retroviral prophylaxis to prevent mother-to-child HIV
transmission (PMTCT). This has a substantial impact on
the death rate in children, with previous gains reversed for
children <5 years of age in several countries.
Without intervention, the risk of mother-to-child HIV
transmission is 30%–35%. With antenatal HIV testing,
combination antiretroviral drugs, and safer infant feeding,
the risk can be reduced to 1%–2%. Simplified short-course
interventions can reduce PMTCT transmission to 15%-
20%. Interventions for PMTCT should also be provided in
the broader context of prevention, including primary pre-
vention of HIV, preventing unintended pregnancies, and
care and support to HIV-infected women and their families.
U.S. Government Response to
Global Mother-to-Child HIV Transmission
In 2002, President George W. Bush introduced the
International Mother and Child HIV Prevention Initiative.
This initiative was coordinated across several U.S. govern-
ment agencies including the Centers for Disease Control
and Prevention (CDC) and U.S. Agency for International
Development. The initiative focused on 14 countries in
Africa and the Caribbean with high rates of HIV/AIDS.
The goals of the initiative were to reduce mother-to-child
transmission by up to 40%; support expanding national
PMTCT programs; support linking PMTCT services with
antiretroviral treatment and care for mothers, infants, and
family members (PMTCT-plus); and reach up to 1 million
women annually.
Core interventions include routinely recommending
HIV counseling and testing at antenatal clinics, short-
course antiretroviral prophylaxis for HIV-positive mother-
infant pairs, counseling and support for safe infant feeding
practices, and counseling for family planning. Additional
interventions include prevention strategies for HIV-nega-
tive pregnant women and community mobilization to
increase uptake and decrease stigma. By 2003, all 14 coun-
tries had started to provide services, and this initiative is
now a major activity under the more comprehensive
President’s Emergency Plan for AIDS Relief, which targets
the same 14 countries plus Vietnam.
Implementing PMTCT Programs Internationally
Case Study in Kenya
Kenya has a population of 31.1 million, with 1.2 mil-
lion births every year. Of the 2.2 million people living with
HIV/AIDS in Kenya, 1.4 million are women. The most
rapidly growing population becoming infected with HIV is
women. HIV-positive women give birth to 118,000 chil-
dren annually. An estimated 35,000–40,000 of those
infants are HIV-positive. Ten percent of reported
HIV/AIDS cases in Kenya are in children <5 years of age.
PMTCT interventions include antiretroviral drug prophy-
laxis, optimal obstetric care, infant feeding counseling, and
family planning. Replacement feeding (as opposed to
breastfeeding) is only recommended in environments
where it is acceptable, feasible, sustainable, and safe.
Through the CDC Global AIDS Program in Kenya, 18,000
antenatal women have learned their HIV status, and 50%
of those who are HIV-positive have received prophylactic
antiretroviral drugs. Barriers to testing include a lack of
spousal support, fear of partner violence, and fear of dis-
closure and the stigma that may accompany it.
Case Study in Botswana
Botswana’s 2003 surveillance data show that 37.4% of
women attending antenatal clinics are HIV-positive.
Botswana has had a national PMTCT program since 2001
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 10, No. 11, November 2004 2027
Conference Session Summaries1
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ed in order topics were discussed. More session summaries are
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and an expanding antiretroviral treatment program since
2002. Both programs are free to patients. All pregnant
women can receive HIV counseling and testing.
Antiretroviral prophylaxis for women and infants and
infant formula are provided for HIV-positive women.
Although 95% of pregnant women attend antenatal clinics
and deliver in health facilities, uptake of PMTCT has been
low. A CDC-Botswana government survey of pregnant
women was performed to explore factors influencing HIV
test acceptance. Factors predicting acceptance included
higher educational level, attendance at urban clinics,
greater knowledge about PMTCT, planned pregnancy, dis-
cussing HIV testing with others, and knowing others who
had received PMTCT or antiretroviral therapy.
These presentations highlight the successes of
PMTCT programs as well as continuing challenges. There
continues to be a need for program evaluation, operational
research, and expanded PMTCT services in order to max-
imally prevent mother-to-child HIV transmission.
Nathan Shaffer,* Michelle McConnell,*
Omotayo Bolu,* Dorothy Mbori-Ngacha,†
Tracy Creek,* Ralph Ntumy,‡
and Loeto Mazhani§
*Centers for Disease Control and Prevention, Atlanta, Georgia,
USA; †Centers for Disease Control Kenya, Nairobi, Kenya;
‡Botswana Ministry of Health National PMTCT Program,
Gaborone, Botswana; and §Nyangabgwe Hospital, Francistown,
Botswana
Address for correspondence: Nathan Shaffer, Global AIDS Program,
Centers for Disease Control and Prevention, 1600 Clifton Rd., Mailstop
E04, Atlanta, GA30333, USA; fax: 404-639-6499; email: nas4@cdc.gov
Infectious Etiologies
of Chronic Diseases:
Focus on Women
Infections can directly or indirectly cause chronic con-
ditions through progressive pathology (e.g., chronic infec-
tion, inflammation, immunity, malignant transformation),
sudden permanent insults (e.g., West Nile virus
poliomyelitis paralysis), or by predisposing people to non-
infectious sequelae (e.g., neurologic consequences of
preterm birth). Bacteria, parasites, prions, viruses, and
fungi may be the single or one of several factors contribut-
ing to chronic disease; one organism can cause more than
one syndrome, and diverse pathogens produce similar syn-
dromes as pathways to disease converge (1). Certain
potential outcomes disproportionately affect women (e.g.,
autoimmune diseases), and in some settings, detection,
prevention, or treatment efforts (e.g., ocular trachoma,
underdiagnosed genital infections) may marginalize
women. Women's activities can also increase exposures to
chronic disease pathogens (e.g., schistosomiasis attributa-
ble to chores or agriculture), and gender can affect trans-
mission (e.g., increased male-to-female transmission of
human T-cell leukemia virus-1). Preventing maternal
infections may further minimize chronic disease and neu-
rodevelopmental disorders in offspring.
Are Women's Autoimmune Diseases
Really Autoimmune?
Systemic and organ-specific autoimmune diseases, such
as rheumatoid arthritis and myocarditis, are the leading
cause of death in women >65 years of age (2). They affect
14–22 million people (5%–8% of the population) in the
United States (3) and millions more worldwide. In autoim-
munity, the immune system may attack or damage self-tis-
sues with autoantibodies and autoreactive T and B cells.
However, the indolent nature of most autoimmune diseases
makes determining infectious triggers difficult. Animal
models help to understand such links. For example, transfer
of disease by autoantibodies and immune cells from affect-
ed animals indicates the immune-mediated nature of these
syndromes (4–6). Toll-like receptors and the innate immune
system, critical components of the normal human response
to infection, are essential to naturally and experimentally
induced autoimmunity. Genetic and other factors affect sus-
ceptibility to both infection and autoimmune disease. For
example, coxsackievirus B3 induces viral myocarditis in
susceptible mice. Certain cytokines (interleukin [IL]-1 and
tumor necrosis factor [TNF]-α), but not viral replication,
correlate with cardiac inflammation and can overcome
resistance to chronic myocarditis (7–9). These findings sug-
gest that, while infection may trigger autoimmunity,
immune processes drive disease progression. Estrogen
amplifies the immune response to coxsackievirus B3 in sus-
ceptible mice, increasing TNF-α and IL-4 levels (unpub.
data), which is perhaps consistent with women's predispo-
sition to autoimmune disease. Identifying triggers, includ-
ing infection, and early markers of autoimmunity are
important goals for preventing onset of or disrupting pro-
gression to autoimmune disease.
Infection Connection in
Neurodevelopmental Disorders
Intrauterine infections are known causes of congenital
defects worldwide. Infections during the time of fetal brain
development might also contribute to neuropsychiatric dis-
orders, including schizophrenia. Studies linking various
gestational insults (including infections) and subtle pre-
morbid behavioral alterations to adult schizophrenia impli-
cate a neurodevelopmental origin. However, the long
2028Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 10, No. 11, November 2004
INTERNATIONAL CONFERENCE ON WOMEN AND INFECTIOUS DISEASES