Hemophilia and other bleeding disorders are characterized by a permanent tendency towards spontaneous or traumatic hemorrhages, which are responsible for significant disease burden and negative impact on quality of life. Hemophilia, an X-linked condition resulting in a decrease or lack of clotting factor VIII (hemophilia A or classic hemophilia) or clotting factor IX (hemophilia B or Christmas disease), is marked by bleeding into joints and muscle, and may also lead to bleeding that results in neurologic damage, damage to other organ systems, or death. Hemophilia occurs in about 1 in 5,000 male births; hemophilia A is about four times as common as hemophilia B.1 Hemophilia affects all racial and ethnic groups. It is estimated there are about 20,000 males with hemophilia in the United States at this time.1,2,3 The severity of an individual’s hemophilia is determined by the amount of factor in their blood. The lower the amount of the factor, the more severe the bleeding disorder and the more likely it is that bleeding may lead to serious health problems.

Approximately 7 in 10 of all persons with hemophilia in the U.S. receive at least some of their care at a federally funded HTC.3 Federally funded HTCs developed a model of care delivery called comprehensive (integrated) care, which includes specialized prevention, diagnostic and treatment programs designed to provide family-centered education, and state-of-the-art treatment, research, and support services for individuals and families living with bleeding disorders. These centers currently provide care to more than 43,000 children and adults with bleeding disorders.4

Since 1998, the Division of Blood Disorders (DBD) has provided support to HTCs for programs designed to monitor and prevent complications of inherited or congenital bleeding disorders. The Universal Data and Serum Specimen Collection (UDC) system for hemophilia, a collaboration between the HTCs and CDC, established a sensitive blood safety monitoring system among people with bleeding disorders and collects a uniform set of clinical outcomes information, which have been used to monitor the occurrence of infectious diseases and joint complications and to assess their potential risk factors. From 1998 to 2011, UDC captured information from more than 97,000 annual visits, representing approximately 27,000 participants. People with bleeding disorders were enrolled in UDC by care providers in each of the approximately 140 federally funded HTCs. HTC staff collected a uniform set of clinical data and blood specimens (plasma or serum) each year during each participant’s annual comprehensive clinic visit. A portion of each specimen was used to perform free screening tests at CDC for hepatitis A, B, and C viruses and HIV. The remainder of the specimen was stored for use, as needed, in future blood safety investigations. Data from UDC have been used to show that, since 1998, no new infections of hepatitis A, B, or C or HIV have been linked to blood products used to treat bleeding disorders. The data from UDC have also been used to describe complications among patients receiving care at HTCs, including the impact of being overweight on joint mobility, the importance of prophylaxis use to reduce intracranial hemorrhage, and the differences in bleeding complications among children younger than 2 years old, compared to older children and adults.

Community Counts is the next generation of bleeding disorder surveillance, and builds upon the information and experience gained through 12 years of UDC data collection. CDC funds the project through a cooperative agreement awarded to ATHN, in partnership with the network of federally funded HTCs. The overall purpose of Community Counts is the same as UDC — to collect and share information about health indicators and complications affecting people with hemophilia and other inherited or congenital bleeding disorders who receive care at federally funded HTCs. The concentration of UDC was primarily joint disease and blood-borne infections. In Community Counts, the concentration includes inhibitors and prophylaxis, quality of life, pain, and co-occurring conditions. Community Counts data will be used to measure rates of bleeding disorder complications and monitor trends over time, identify high-risk populations for programs to prevent complications, and identify issues that require further study. Community Counts consists of three components:

  • HTC Population Profile (HTC PP) gathers basic information on all HTC patients with bleeding disorders or blood clots. The goal of the HTC PP is to learn basic information about HTC patients, such as how many receive care at the HTCs.
  • Registry for Bleeding Disorders Surveillance (the Registry) gathers detailed information over time on the characteristics, diagnoses, risk factors, and complications of HTC patients with bleeding disorders.
  • Mortality Reporting tracks the characteristics, diagnoses, and causes of death of HTC patients with bleeding disorders who have died.


  1. Soucie JM, Evatt B, Jackson D, and the Hemophilia Surveillance System Project Investigators. Occurrence of hemophilia in the United States. American Journal of Hematology. 1998;59:288–294.
  2. Siddiqi AA, Ebrahim SH, Soucie JM, Parker CS, Atrash HK. Burden of disease resulting from hemophilia in the U.S. Am J Prev Med 2010;38(4S):S482–S488.
  3. Baker JR, Riske B, Drake JH, Forsberg AD, Atwood R, Voutsis M, Shearer R. US Hemophilia Treatment Center population trends 1990–2010: patient diagnoses, demographics, health services utilization. Haemophilia. 2013;19:21-6.
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