Human Papillomavirus Vaccination Strategies

To the Editor: An article by Elbasha et al. in the January 2007 issue of Emerging Infectious Diseases showed an economic evaluation of human papillomavirus (HPV) vaccination strategies (1). In this model, incremental cost-effectiveness ratio (ICER) calculations were based on costs measured as US dollars for 2005 and effectiveness measured as quality-adjusted life years (QALYs). Authors presented these data transparently and showed costs and QALYs of each strategy in 2 tables, where they did not show ICER of dominated options; i.e., “Strategy A is dominated if there is another strategy, B, that is more effective and less costly than strategy A” (1). Unfortunately, splitting data into 2 tables can be misleading. 
 
First, ICERs of strategies for vaccination at the age of 12 (70% coverage) compared with a strategy of no vaccination showed that the strategy of vaccinating 12-year-old girls and boys is dominated by other strategies. Furthermore, vaccination of 12-year-old girls only and vaccination of 12-year-old girls only with catch-up (vaccination of girls and women 12–24 years of age) have lower ICERs, which could be interpreted as the most cost-effective approaches. 
 
Finally, ICERs of strategies of vaccinating at 15 and 18 years of age (50% coverage) are presented without comparison strategies. Thus, one might assume that these strategies are compared with the baseline strategy (vaccination of 12-year-old girls only); however, they are compared with the no-vaccination strategy. 
 
The transparency of the Elbasha et al. article enabled us to build a new table based on their data (Table). In our table, ICERs of the whole set of strategies showed that vaccination of 12-year-old girls only is dominated by the vaccination of 18-year-old women plus a catch-up strategy (women 18–24 years of age), although older groups have lower coverages. 
 
 
 
Table 
 
Cost-effectiveness analysis of alternative human papillomavirus vaccination strategies* 
 
 
 
In addition, I point out 2 particulars. First, epidemiology of HPV varies between countries (2), probably because of differences in culture and sexual habits. Thus, vaccination at older ages should be considered in countries in which prevalence of adolescent sexual activity or HPV is low. Second, higher vaccine coverage in older groups would decrease ICERs of these strategies (1). Both facts could reflect the real situation in some countries, e.g., Spain (2,3). 
 
In conclusion, economic evaluations of HPV vaccination strategies should have broader sensitivity analysis to include as many country-specific realities as possible. To avoid misunderstandings that could lead policymakers to misallocate funds, these results should be evident to readers.

with no adverse effects reported. One patient treated herself with albendazole (400 mg/day for 3 days) before she was seen at a hospital. All patients became asymptomatic and had negative stool examination results 2-10 weeks after treatment.
None of the patients reported previous or subsequent consumption of raw freshwater fi sh. Raw fi sh preparations such as sushi, sashimi, carpaccio, and ceviche are increasingly popular and are now also prepared with local freshwater fi sh. These new food habits represent a clear risk factor for human infection (5,7).
The plerocercoid larvae in the fi sh muscles are easily missed during food preparation. Nor are local fi sh systematically inspected, as imported fi sh are. The role of paratenic hosts (e.g., dogs, foxes) in transmission is not fully understood.
Information given to the public and professionals such as food handlers, restaurant owners, and fi shermen is a key measure to promote safer food practices. Avoiding serving preparations of raw freshwater fi sh or selecting fi sh that are not intermediate hosts of D. latum would decrease parasite transmission. Cooking the fi sh at 55°C for 5 minutes effi ciently kills the larvae. Freezing the fi sh at -20°C for 24 hours is also effi cient. International regulations recommend freezing all fi sh that are expected to be served raw. Notable exceptions are fi sh from farm culture or from areas where strong evidence proves no source or cases of infection (European community rules 853/2004 annexe III, available from www.paquethygiene. com/reglement_ce_853_2004/regle-ments_ce_853_2004_du_parlement_ europeen_et_du_conseil_annexe_ 3_section_8.asp#debut).
However, enforcing these rules proves very diffi cult for food safety administrations.

Human Papillomavirus Vaccination Strategies
To the Editor: An article by Elbasha et al. in the January 2007 issue of Emerging Infectious Diseases showed an economic evaluation of human papillomavirus (HPV) vaccination strategies (1). In this model, incremental cost-effectiveness ratio (ICER) calculations were based on costs measured as US dollars for 2005 and effectiveness measured as qualityadjusted life years (QALYs). Authors presented these data transparently and showed costs and QALYs of each strategy in 2 tables, where they did not show ICER of dominated options; i.e., "Strategy A is dominated if there is another strategy, B, that is more effective and less costly than strategy A" (1). Unfortunately, splitting data into 2 tables can be misleading.
First, ICERs of strategies for vaccination at the age of 12 (70% coverage) compared with a strategy of no vaccination showed that the strategy of vaccinating 12-year-old girls and boys is dominated by other strategies. Furthermore, vaccination of 12year-old girls only and vaccination of 12-year-old girls only with catch-up (vaccination of girls and women 12-24 years of age) have lower ICERs, which could be interpreted as the most cost-effective approaches.
Finally, ICERs of strategies of vaccinating at 15 and 18 years of age (50% coverage) are presented without comparison strategies. Thus, one might assume that these strategies are compared with the baseline strategy (vaccination of 12-year-old girls only); however, they are compared with the no-vaccination strategy.
The transparency of the Elbasha et al. article enabled us to build a new table based on their data (Table). In our table, ICERs of the whole set of strategies showed that vaccination of 12-year-old girls only is dominated by the vaccination of 18-year-old women plus a catch-up strategy (women 18-24 years of age), although older groups have lower coverages.
In addition, I point out 2 particulars. First, epidemiology of HPV varies between countries (2), probably because of differences in culture and sexual habits. Thus, vaccination at older ages should be considered in countries in which prevalence of adolescent sexual activity or HPV is low. Second, higher vaccine coverage in older groups would decrease ICERs of these strategies (1). Both facts could refl ect the real situation in some countries, e.g., Spain (2,3).
In conclusion, economic evaluations of HPV vaccination strategies should have broader sensitivity analysis to include as many country-specifi c realities as possible. To avoid misunderstandings that could lead policymakers to misallocate funds, these results should be evident to readers. After these epidemics, the viruses disappeared and no marine or terrestrial reservoirs have been identifi ed.

Santiago Pérez Cachafeiro*
In January 2007, a moribund, subadult, white-beaked dolphin (Lagenorhynchus albirostris) was found stranded on the North Friesian coast of Germany. The animal was humanely

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