The cost-effectiveness of neonatal versus prenatal screening for congenital toxoplasmosis.

BACKGROUND: Congenital Toxoplasmosis (CT) can have severe consequences. France, Austria, and Slovenia have prenatal screening programs whereas some other countries are considering universal screening to reduce congenital transmission and severity of infection in children. The efficiency of such programs is debated increasingly as seroprevalence among pregnant women and incidence of congenital toxoplasmosis show a steady decrease. In addition, uncertainty remains regarding the effectiveness of pre- and postnatal treatments. METHOD: To identify cost-effective strategies, prenatal and neonatal screenings were compared using a decision-analytic model based on French guidelines and current knowledge of long-term evolution of the disease in treated children. Epidemiological data were extracted from the scientific literature and clinical data from the French Lyon cohort. Strategies were compared at one year of age, when infection can be definitively evaluated, and at 15 years of age, after which validated outcome data become scarce. The analysis was performed from the French Health Insurance System perspective and included direct medical costs for pregnant women and their children. RESULTS: The 1-year Incremental Cost-Effectiveness Ratio showed that prenatal screening would require investing €14,826 to avoid one adverse event (liveborn with CT, fetal loss, neonatal death or pregnancy termination) compared to neonatal screening. Extra investment increased up to €21,472 when considering the 15-year endpoint. CONCLUSIONS: Prenatal screening is cost-effective as compared to neonatal screening in moderate prevalence areas with predominant Type II strains. In addition, prenatal screening, by providing closer follow-up of women at risk increases the number of occasions for education avoiding toxoplasmosis.

Congenital toxoplasmosis in Austria: Prenatal screening for prevention is cost-saving.

BACKGROUND: Primary infection of Toxoplasma gondii during pregnancy can be transmitted to the unborn child and may have serious consequences, including retinochoroiditis, hydrocephaly, cerebral calcifications, encephalitis, splenomegaly, hearing loss, blindness, and death. Austria, a country with moderate seroprevalence, instituted mandatory prenatal screening for toxoplasma infection to minimize the effects of congenital transmission. This work compares the societal costs of congenital toxoplasmosis under the Austrian national prenatal screening program with the societal costs that would have occurred in a No-Screening scenario. METHODOLOGY/PRINCIPAL FINDINGS: We retrospectively investigated data from the Austrian Toxoplasmosis Register for birth cohorts from 1992 to 2008, including pediatric long-term follow-up until May 2013. We constructed a decision-analytic model to compare lifetime societal costs of prenatal screening with lifetime societal costs estimated in a No-Screening scenario. We included costs of treatment, lifetime care, accommodation of injuries, loss of life, and lost earnings that would have occurred in a No-Screening scenario and compared them with the actual costs of screening, treatment, lifetime care, accommodation, loss of life, and lost earnings. We replicated that analysis excluding loss of life and lost earnings to estimate the budgetary impact alone. Our model calculated total lifetime costs of €103 per birth under prenatal screening as carried out in Austria, saving €323 per birth compared with No-Screening. Without screening and treatment, lifetime societal costs for all affected children would have been €35 million per year; the implementation costs of the Austrian program are less than €2 million per year. Calculating only the budgetary impact, the national program was still cost-saving by more than €15 million per year and saved €258 million in 17 years. CONCLUSIONS/SIGNIFICANCE: Cost savings under a national program of prenatal screening for toxoplasma infection and treatment are outstanding. Our results are of relevance for health care providers by supplying economic data based on a unique national dataset including long-term follow-up of affected infants.

Maternal serologic screening to prevent congenital toxoplasmosis: a decision-analytic economic model.

OBJECTIVE: To determine a cost-minimizing option for congenital toxoplasmosis in the United States. METHODOLOGY/PRINCIPAL FINDINGS: A decision-analytic and cost-minimization model was constructed to compare monthly maternal serological screening, prenatal treatment, and post-natal follow-up and treatment according to the current French (Paris) protocol, versus no systematic screening or perinatal treatment. Costs are based on published estimates of lifetime societal costs of developmental disabilities and current diagnostic and treatment costs. Probabilities are based on published results and clinical practice in the United States and France. One- and two-way sensitivity analyses are used to evaluate robustness of results. Universal monthly maternal screening for congenital toxoplasmosis with follow-up and treatment, following the French protocol, is found to be cost-saving, with savings of $620 per child screened. Results are robust to changes in test costs, value of statistical life, seroprevalence in women of childbearing age, fetal loss due to amniocentesis, and to bivariate analysis of test costs and incidence of primary T. gondii infection in pregnancy. Given the parameters in this model and a maternal screening test cost of $12, screening is cost-saving for rates of congenital infection above 1 per 10,000 live births. If universal testing generates economies of scale in diagnostic tools-lowering test costs to about $2 per test-universal screening is cost-saving at rates of congenital infection well below the lowest reported rates in the United States of 1 per 10,000 live births. CONCLUSION/SIGNIFICANCE: Universal screening according to the French protocol is cost saving for the US population within broad parameters for costs and probabilities.

[Evaluation of prevention strategies for congenital toxoplasmosis: a critical review of medico-economic studies]. / Evaluation de stratégies de prévention de la toxoplasmose congénitale: revue critique des études médico-économiques.

BACKGROUND: Congenital toxoplasmosis (CT) may lead to serious neurological or sensory consequences. A serological screening of women at risk of acquiring toxoplasmosis became mandatory in France, first during the visit before wedding (1978), then during the visit for pregnancy declaration (1985) and at last with a monthly follow-up during pregnancy since 1992. The efficacy and the profitability of the program was never assessed, in spite of the modification of the epidemiological context. However medico-economical studies were conducted in countries in which no prevention program for CT was available to determine the interest of an antenatal screening similar to the French one or of other prevention strategies. METHODS: Eight studies comparing at least two strategies were selected. Methodologies used in those studies were analyzed by two independent readers with the help of a standardized scale. A score was calculated for each study. RESULTS: Each study analyzed suffered from methodological limitations, in particular concerning the estimation of antenatal treatment efficacy, which could lead to invalidate their conclusion. The most reliable studies in regard to methodological guidelines, that is with the higher score, concluded that antenatal screening was not contributive. However, they could not be transposed directly in the present French situation, because of the difference of the epidemiological and economical context. CONCLUSIONS: Given the difficulty to obtain a clear conclusion, it seems necessary to perform a rigorous decision analysis to identify the more effective and acceptable program in terms of human and financial costs for preventing congenital toxoplasmosis.

Prevention of congenital toxoplasmosis in Slovenia by serological screening of pregnant women.

A programme for the prevention of congenital toxoplasmosis in Slovenia involving the screening of pregnant women for Toxoplasma infection is presented. Of 21,270 pregnant women screened for toxoplasmosis between, 1996 and the end of 1999, 13,987 (66%) were seronegative, 7,151 (34%) seropositive and 132 had primary infection; approximately 9/1,000 women were at risk of acquiring the primary infection. One hundred live-born infants of primary infected women were available for follow-up. Nine infected but asymptomatic children were born to mothers who were screened and treated in time and two congenitally infected babies were born to mothers in whom infection was detected too late in pregnancy and who therefore received no adequate treatment. It is suggested that the results obtained in this study outweigh the cost of screening for toxoplasmosis in pregnancy. Pregnant women should always be tested at the beginning of pregnancy and, in cases of seronegativity, should be re-tested in the second and third trimesters of the pregnancy. Toxoplasma primary infected pregnant women and neonates should be treated as soon as possible. However, long-term follow-up of children born to primary infected women would be necessary for an accurate evaluation of the effectiveness of the screening because of the possibility of late onset of symptoms.

[Cost-benefit analysis of screening for congenital toxoplasmosis]. / Kosten-Nutzen-Analyse des Screenings auf kongenitale Toxoplasmose.

A comprehensive cost-benefit analysis of possible screening strategies for congenital toxoplasmosis is necessary as a basis for the decision whether or not screening is efficient and socially desirable. The total costs of the disease in Switzerland were calculated for the year 1990. Direct costs (all diagnostic and therapeutic interventions, including care of handicapped children) and indirect costs (partial and total work losses in the future) were taken into account. Today, the direct costs amount to approx. SFr. 20 mio per year (i.e. approx. SFr. 2.8 mio per million population). The indirect costs were calculated at SFr. 4 mio per year. Moreover, the costs incurred with three possible screening programs (1 test with all pregnant women, with 1, 2 or 5 additional tests, depending on the strategy) were estimated, together with the concomitant cost savings. The financial resources needed for the screenings would amount to SFr. 7 mio-18 mio per year, depending on the strategy chosen. However, the possible savings would be in the range of SFr. 4 mio-12 mio only. The possible savings are, in any case, of the same order of magnitude as the costs for screening. Screening would become cost-efficient if costs for the serological tests could be lowered.

Cost-benefit analysis of screening for toxoplasmosis during pregnancy.

Congenital toxoplasmosis is a risk for fetus both in 'low' and 'high risk' areas. A cost-benefit analysis based on data from a Finnish prospective study (20.3% seropositivity of pregnant mothers and incidence of 2.4/1,000 seronegative pregnancies) and on Finnish cost data was performed to compare the no-screening and screening alternatives for primary toxoplasma infections during pregnancy. A maternal-feto transmission risk of 40%, effectiveness of treatment of 50%, and discount rate of 4% were used as other baseline probabilities. The calculations were carried out by decision analysis combined with sensitivity analysis. The total annual costs of congenital toxoplasmosis without screening amount to US$ 128/pregnancy/year, and with systematic serological screening, US$ 95/pregnancy. Thus screening reduces the costs by 25%. The present value of net savings in Finland would be US$ 2.1 million every year. A one-way sensitivity analysis showed that screening together with health education is preferable to health education without screening if the incidence of maternal primary infections exceeds 1.1/1,000 and effectiveness of treatment is better than 22.1%. Screening for toxoplasma infections during pregnancy is economically worthwhile even in a country with a low incidence. A scheme of systematic screening for maternal primary toxoplasma infections combined with health education should be considered.

Economic evaluation of preventive programmes against congenital toxoplasmosis.

Benefit-cost analysis are applied to different strategies aimed at preventing congenital toxoplasmosis. The first strategy involves health education of pregnant women on how to avoid toxoplasma infection. The second strategy comprise serological surveillance in pregnancy combined with prenatal diagnosis and chemotherapy. The cost of health education is less than the cost of the serological screening, but health education will most likely lead to a haphazard testing of individuals and thereby increasing the cost. The best and most rational approach, and the programme which will prevent most cases and save most money for the society, is a combination of both programmes. Compared with the results of any of the two strategies alone, the benefits of the combined programme will increase significantly, while the cost (NOK 165 per participating woman) will only add fractions to that of the serological screening programme. The benefits of the strategies are influenced by many uncertain factors such as the discount rate, the incidence of infection, the intrauterine transmission rate, the outcome of pregnancy, the prognosis of the offspring, the sensitivity of the screening tests and the effectiveness of the programme. After applying a sensitivity analysis, both programmes were found to be of economic benefit to society at an incidence of maternal toxoplasmosis of 1-1.5 per 1000. Thus the pilot screening initiated in Norway to determine the incidence of infection, seems justified.

Congenital toxoplasmosis: to screen or not to screen?

We have reviewed the present day quantifiable cost to society of the 73 cases of congenital toxoplasmosis which are estimated to occur annually in Scotland with the cost of preventing the disease by screening and treatment. Our analysis includes advances in laboratory techniques. The cost of screening would depend on its scale and if in-house or commercial tests are used. If only 2 specimens were screened, at booking and at delivery, the screening costs are estimated to be between 0.5-0.9 times the preventable costs. If a third specimen were tested in the second trimester, to maximise scope for remedial action during pregnancy, the screening costs are 0.7-1.2 times preventable costs. As likely screening costs in most of the schemes we consider are now less than the preventable costs, a screening programme should be adopted.

The impact of zoonotic diseases transmitted by pets on human health and the economy.

In the context of all causes of human morbidity and mortality, or even within the context of all infectious diseases affecting the public health, pet-associated zoonotic infections are of moderate importance. The data documented in Table 1, however, indicate that they do exact significant human health and economic costs. If complete data were available for all of the infections shown in Table 1, the costs would be considerably higher. Moreover, most of these diseases are preventable through educating the public, particularly pet owners, of the zoonotic potential of these diseases, so that they may take precautions to minimize the risks leading to infection. These measures include appropriate health care of pets to eliminate infectious agents, reducing the number of uncontrolled, ownerless pets as well as unwanted or poorly supervised pets, preventing pets from soiling public places with their feces, excluding animals from areas where children play, enforcing leash laws, and promoting responsible pet ownership. Veterinarians, physicians, and public health agencies can aid in these efforts; ultimately, however, the responsibility lies with the pet owner.

What can be done to prevent congenital toxoplasmosis?

There is a great deal of confusion within the medical and lay communities regarding Toxoplasma infection in the pregnant woman. Many physicians are not aware of the significance of this infection in pregnant women or of measures that may decrease the likelihood of the birth of an infant with congenital toxoplasmosis. Data regarding the morbidity, incidence, cost, and measures for the prevention of congenital toxoplasmosis are discussed.