Update - November 2004
VVMs have been available on oral polio vaccine since 1996
VVM uptake:accelerating in international markets but lagging behind in domestic markets.
New data on the introduction of vaccine vial monitors (VVMs) – which are designed to prevent the use of heat-damaged vaccine and avoid waste – reveal that while global uptake has doubled over the past year, there is a big gap between their use in international and domestic markets. Sheila Davey reports.
While VVMs are increasingly supplied on vaccines purchased for the international market through UNICEF, they are not yet available on many of the non-polio vaccines produced in developing countries for domestic markets.
In 2004, almost one-third of the doses of non-polio vaccine purchased and supplied to the international market through UNICEF will have a VVM label attached. By 2005, 100% implementation is expected to be reached on 7 of the 12 vaccines bought by UNICEF (excluding DTP-Hib and meningitis A/C, which are bought in very small volumes). In addition, three others will be at or above 80% implementation, leaving only two with lower implementation (see Figure 1).
The VVM – a label that registers exposure to heat over time -- has been available on oral polio vaccine since 1996. However, the implementation of the device by manufacturers was more complicated than envisaged, says Stephen Jarrett, Deputy Director of UNICEF’s Supply Division. “As a result, the uptake of the device on other vaccines has been slower than originally anticipated,” he explained. “One of the reasons has been that UNICEF is the only committed buyer of vaccines with VVMs.”
| Figure 1: VVMs on vaccines supplied through UNICEF 2004-2006 - Source:UNICEF|
In 2002, the GAVI Board stipulated that from the beginning of 2004 all vaccines purchased through The Vaccine Fund must include VVMs – a target that will be met this year, with the exception of yellow fever vaccine. Of the 25 vaccine manufacturers prequalified to supply vaccines through the UN – including five suppliers of oral polio vaccine - 16 have now included VVMs (as of June 2004).
However, John Lloyd of PATH, which gathered the new data on the implementation of VVMs worldwide (see Figure 2), is concerned that while the international manufacturers have made tremendous progress in the use of VVMs, national manufacturers are lagging behind. “As a result,” he says, “a huge proportion of domestically-supplied non-polio vaccines in vaccine-producing countries are still being distributed without VVMs.”
Manufacturers in Latin America and South East Asia have been especially slow to comply – in some cases because governments have not yet asked them to do so when supplying vaccine for domestic markets. In the Americas, the Pan American Health Organization (PAHO) has not advised countries to make VVMs a requirement.
Developing country manufacturers which supply both international and national markets are now moving towards the wider use of VVMs in domestic markets. However, those producing exclusively for domestic markets are making less progress. The added cost of VVMs remains a barrier, especially in lowincome countries where the price of the basic children’s vaccines is often relatively low and the added cost of the VVM significantly greater than in industrialized countries, where vaccine prices are higher. UNICEF estimates that in 2004-2006 the VVM will add over 1 US cent on average to the cost of a vaccine dose. While this adds less than 1% to the cost of DTP-HepB vaccine, it represents an 8% increase on the average price of tetanus toxoid vaccine.
Figure 2: Global VVM implementation by vaccine dose 2003-2004 - Source: PATH/Time Temp, USA
UNICEF and WHO estimate that the use of VVMs on the basic vaccines alone could save about US$5 million a year. Their use on more expensive vaccines such as Hib and hepatitis B could generate even greater savings. A study carried out in Bhutan in 1997-98 by WHO and the Government of Bhutan found that when VVMs were used to implement the WHO multidose vaccine vial policy they helped reduce wastage on polio vaccine by almost 50%.
However, John Lloyd points out that VVMs are not a panacea. Even when they are supplied on all vaccines, health workers need training on how to use them correctly, including the critical need to monitor vaccine wastage in order to identify problems in the cold chain. “We need to establish proper systems for training, supervision and monitoring in order to make the system work,” he warned, “and unfortunately that isn’t happening yet.”Immunization Forum November 2004 -