Despite Vaccine, Tetanus a Problem for Newborns in Remote Areas
With the target date for elimination of neonatal tetanus about to pass, the disease remains a major public health problem in remote areas of Africa and Asia, despite an international campaign to eliminate the often-fatal illness and despite having a vaccine that works.
Neonatal tetanus is common where infants' umbilical cords are cut with unsanitary instruments. The vaccine used to prevent tetanus in women of childbearing age and their newborns is effective, according a new systematic review of data.
The low performance of the vaccination campaign is "probably related to organizational and quality issues," according to a new systematic evidence review.
The authors located only two studies that met the quality criteria for the review, and both were conducted more than 25 years ago. Nevertheless, "these were reasonably good studies, quite large, both confirming that the vaccine was effective," says lead author Dr. Vittorio Demicheli, an Italian epidemiologist.
The review appears in the most recent issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
The reviewers identified two experimental studies involving 10,560 infants born to 95,704 immunized individuals in Colombia and Bangladesh. Conducted in the 1960s and 1970s respectively, the studies confirmed that two or more doses of the vaccine are highly effective in preventing deaths from neonatal tetanus.
In 1989, the World Health Organization and other groups launched an international vaccination campaign targeting women of childbearing age, who then pass immunity to their unborn children.
The goal of the campaign was to eliminate neonatal tetanus by 1995, a date that was eventually pushed back to 2005. Significant progress has been made, yet neonatal tetanus remains a major public health problem in 52 countries, according to WHO.
According to the review authors, it's possible that vaccines are not being stored properly, or that factors such as malaria preventatives, malnutrition or vitamin A deficiency are interfering with its effectiveness.
"Future research should concentrate on evaluating these and other factors that may have a negative impact on the immunization practice," say the authors. Demicheli adds that such research will require "specific studies in specific places, because the explanation could be different in different settings."
Meanwhile, WHO is counting on more convenient injection technologies and a new single-dose vaccine. These will offer "immense value in simplifying maternal [tetanus] immunization programs in developing countries," says the organization's website.