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Public health

Breathing spell for the vaccine

Specialists declare 2007 the year of the fight against pneumococcal disease

cdcMicroscope image reveals invasion by Streptococcus pneumoniaecdc

Winnie is 3 months old and fights to breathe – the tube of oxygen that goes into her nostril is not much use. Her wide-open eyes are the living portrait of her panic when facing a battle that is almost lost against pneumococcal disease, the main cause of death by bacterial pneumonia and meningitis. This scene, which takes place in an undefined African country, but which could occur in any developing country, is in the video produced by pneumoADIP, an American organization that advocates ample access to the pneumococcal vaccine for children from all over the world. The images were repeated nonstop in the entrance hall of the Second Regional Pneumococcal Symposium, which in December brought together physicians, representatives of the pharmaceutical industry, and people responsible for the public health authorities of South, Central and North America. The leaflet distributed at the end of the symposium declares 2007 as the year of action to combat pneumococcal disease in the continent, but the battle will be difficult – not only because of the bacterium in itself, but because of the high price of the vaccine, around US$ 50 per dose.

In Latin America, only Brazil and Mexico have included it in – limited – vaccination programs. In 2005, the Brazilian government distributed 36 thousand doses to immunize children who are vulnerable due to other health problems. Vaccinating this minority has little effect from the point of view of public health, but Luiza de Marilac, the coordinator of the Ministry of Health’s National Immunization Program, calculates that to protect against pneumococcus the 3.2 million children who are born in the country every year, it would be necessary to double the budget that the program has available for acquiring the vaccines. Produced only by the Wyeth laboratory, it is the most expensive of the basic children’s vaccines. The expectation is for the price to fall when it is produced by other manufacturers – one will be launched by GSK in 2008 -, but it cannot yet be affirmed whether it will be sufficiently cheaper to make the vaccine viable for integration into the calendar for all Brazilian children.

Wyeth’s vaccine has existed since 1999 and has now been adopted in the United States, where the children began to be immunized at the end of 2000. During the symposium, Cynthia Whitney, head of the Respiratory Diseases Section of America’s Centers for Disease Control and Prevention (CDC), reported the results of the implementation of the vaccine in her country. From 2000 to 2005, there was a 98% fall in the cases of blood infection and meningitis caused by the types of the Streptococcus pneumoniae bacterium present in the vaccine, and was also successful against pneumonia and otitis in the middle ear. But the surprising thing, according to the doctor, was to observe a reduction in the number of cases in adults – who were not vaccinated. It is what the doctors call the herd effect: vaccinating children interrupts transmission to the older and, in the United States, prevented a good deal of the transmission to adults more than 65 years old. The vaccination campaign surpassed expectations, according to Cynthia, who commemorates the correct decision to include the pneumococcal vaccine in the immunization calendar.

Dissimulated enemy
Streptococcus pneumoniae, better known as pneumococcus, is responsible for lethal diseases like pneumonia and meningitis, besides otitis that can cause deafness. Pneumococcal diseases kill almost 1 million children a year, 90% of them in developing countries. In Latin America alone, two children die every hour, and each year 1.6 million people develop diseases caused by the bacterium. In Brazil, there is a lack of data about its incidence, but 750 thousand persons were interned for pneumonia in 2005, where it is estimated that 40% of the cases were caused by pneumococcus, says Expedito Luna, the director of the Ministry of Health’s Epidemiological Surveillance Department.

As the bacterium is responsible for various diseases and they all can be caused by other agents, it is difficult to make a precise evaluation of its prevalence. “There is not one disease in which the doctor can recognize pneumococcus just with a clinical examination”, explains Gabriel Oselka, a pediatrician from the University of São Paulo (USP) and a member of the Ministry of Health’s Technical Advisory Committee on Immunization.  It is for that reason that concrete data is scarce in Brazil: there is a lack of resources for isolating the bacterium and spotting it in all the case that arrive at the hospitals. Hence, according to Luna, only 11 thousand cases of pneumococcus were diagnosed in 2005 in Brazilian hospitals. As in general the treatment is prescribed without knowing the enemy, pneumococcal diseases are treated with broad-spectrum antibiotics that induce the formation of lineages of Streptococcus pneumoniae that are resistant to the medicines. That is why the best way of fighting it is the vaccine.

Although the economic limitations are real, Jon Andrus, of the Pan American Health Organization (PAHO) believes that the greatest obstacle to the acquisition of vaccines is a not very enterprising mentality. “There is so much data and information that now we have to look back and ask: ‘why not?'”, he argued. The challenge is to define a price that is accessible to all countries, and they will next have to make an effort to obtain funds.   The problem then ceases to be scientific and becomes political; to try to solve it, PAHO intends to promote contacts between finance and health ministers from Latin American countries. Under negotiation is an encounter during the meeting of the World Bank in Guatemala, in April, that for Andrus will be an opportunity for convincing the government authorities that “the death of one child is more important than the death of a cow from foot and mouth disease”.

José Ignácio Santos, the director of the Federico Gómez Children’s Hospital, in Mexico, also stressed the need for reaching agreements between public and private entities. “Success depends on creativity and on the capacity to convince the decision takers”, he said. The course most defended during the symposium involves getting finance from public and private institutions, like PAHO?s Revolving Fund, which helps and defrays the costs of the associated companies in the acquisition of vaccines. Or then the Global Alliance for Vaccines and Immunization (Gavi), which gives support to the 75 poorest countries (with a per capita GDP of less than US$ 1 thousand), seven of them Latin American. As the opportunities for financing are unequal amongst nations, Roberto Tapia-Conyer, who until November 2006 was Mexico’s Vice-Minister of Health, stressed the need for finding alternative schemes for intermediate countries like Brazil ? which do not have access to Gavi, nor boast sufficiently strong economies to bear the costs of the vaccine.

If there were no cost limitations, Oselka thinks that there would be no doubt as to the adoption of the vaccine against pneumococcus. “But there are other things at stake, other priorities”, he counters. Taking into account costs and benefits, he foresees that the vaccines against meningococcus C and chicken pox will be the next ones to enter the Brazilian immunization calendar. They are diseases that are common in Brazil, which can be detained by simpler and cheaper vaccination schemes. To determine an action plan for Brazil, the Ministry of Health has ordered a survey of cost-effectiveness, which evaluates the implementation cost in relation to the onus that the diseases place on society and on the health system, Luiza de Marilac explained. This evaluation should be ready in the next few months and will act as a guide for defining the next vaccines to make up the National Immunization Program. A careful planning is essential, Luna stressed, for the decisions to be sustainable in the long term.