AIDS/Hepatitis, and tuberculosis: implications for the dentist and dental profession

Dentists worlwide treat and manage patients with a variety of oral and systemic complaints. Bacterial fungal and viral infections are commonly seen in dentist practice. Although primarily sexually transmissible, serious diseases such as hepatitis B, herpes, HIV/AIDS and tuberculosis are the major infections for which the dentist must reduce or eliminate the risk of transmission. The best approach to minimize cross-infection to, or from, a patient or other health care worker (HCW) is to use "Universal Precautions" that is, to treat every patient as if they were a carriers of some infection. However, unlike infection control strategies of developed countries, in developing countries these precautions may need to be modified to match the socioeconomic constraints of the region. Governments and HCWs should work together to make vaccinations against hepatitis B a national priority, and improve the education of patients and colleages concerning the risks from all STDs including HIV/AIDS, hepatitis B and tuberculosis. (AU)

Infection par le virus C des hepatites au Sud-Cameroun : des aspects epidemiologiques originaux

Les auteurs rapportent ici les resultats de trois enquetes sero-epidemiologiques menees au Sud-Cameroun dans la Province du Sud en 1990-1991 a Djoum; en 1993 a Mekas et dans la Province de l'Est en 1994 a Yokadouma. Ces trois regions se caracterisent par une population stable; homogene; divisee en deux grands groupes; le groupe Bantou (Bulus; Kakas; Fang; etc) et celui des pygmees. Il ressort donc de ces enquetes que le Sud-Cameroun constitue une zone de tres haute sero-prevalence VHC. Mais les modes connus de transmission du virus; vectoriel; et/ou des facteurs comportementaux; simples hypotheses aujourd'hui; montrent bien qu'il y a encore des inconnues sur l'epidemiologie de l'infection par VHC en Afrique Centrale

Surto de malária induzida entre usuários de drogas injetáveis / Outbreak of malaria among injectable-drugs users

Em julho de 1990, foi registrado na cidade de Bauru, Estado de Säo Paulo, Brasil, um surto de malária envolvendo usuários de cocaína injetável. Uma ampla investigaçäo epidemiológica, conduzida de 19 de julho a 13 de setembro, revelou que pelo menos 119 pessoas estavam envolvidas no surto, uma vez que haviam compartilhado seringas e agulha com um ou mais casos confirmados nos 3 meses anteriores à ocorrência. Cento e duas dessas pessoas foram localizadas e entrevistadas, e destas, 99 foram submetidas a exame de gota espessa e 91 a exames sorológicos para malária. Foram confirmados por exames hemoscópico 21 casos de malária por P. vivax, e 3 outros tiveram exame sorológico positivo para P. vivax. O controle da transmissäo doi obtido fornecendo-se cloroquina aos envolvidos no surto, numa dose inicial de 10 comprimidos, seguida de doses supressivas semanais de 2 comprimidos até que fosse identificado o último comunicante. Amostras de soro coletadas na ocasiäo revelaram, ao lado da malária, uma alta prevalência de infecçöes pelo HIV (58 por cento) e pelo vírus da hapatite B (40 por cento). Foram discutidas as dificuldades para o controle do surto e a possibilidade da malária vir a se tornar uma doença endêmica entre usuários de drogas injetáveis, no Estado de Säo Paulo

Occupational biohazards affecting clinical engineers & BMETs. Part III: Blood and other body fluids.

Results of a previously reported survey of BMETs and CEs indicated a need for further education of these professionals concerning work-related biohazards. In this third article of a five-part series, the dangers of disease transmission by blood and other body fluids are discussed. Susceptibility factors are cited to indicate those persons at greatest risk of infection, and recommendations are provided to assist BMETs and CEs in effectively protecting both themselves and other clinical and nonclinical personnel from infection. The recommendations presented include suggested disinfection procedures for contaminated equipment. Persons interested in further information are advised to contact the infection control officer at their facility, or the Centers for Disease Control.

Estudio sobre transmisiòn perinatal del virus B de la hepatitis en un hospital Ginecoobstétrico de Ciudad de La Habana / Study on perinatal transmission of virus B of hepatitis in a Ginecologic and Obstetric Hospital; Havana City

Se estudiaron 2 000 gestantes a término que parieron entre los meses de septiembre y diciembre de 1986 en el Hospital Ginecoobstétrico Docente "Eusebio Hernández" de Ciudad de La Habana. Todas las gestantes y los hijos de las madres positivas fueron investigados para la determinación de Ags HB por la técnica de ELISA. Adicionalmente se investigó en los seropositivos al primer marcador de Age HB. Los hijos de las madres positivas fueron seguidos clínica y serológicamente durante 4 meses. El índice de positividad de las madres estudiadas fue de 0,4%, y el índice de transmisión perinatal fue de 28,6% Se confirma la gran importancia que tiene la presencia del Age HB para la transmisión del virus B de la hepatitis al elevarse el índice de transmisión al 100% entre las que tenían este marcador. Se considera la importancia relativa que tiene esta vía de transmisión para el mantenimiento de la prevalencia de portadores del Ags HB en nuestro país

[Autotransfusion]. / Autotransfusion.

The risk of contracting certain disorders following a blood transfusion is currently becoming worrisome not only for physicians who are aware of this problem, but also for patients who, with increased media attention on AIDS, are more afraid of this potential risk than of the surgical or anesthetic risks. In fact, hepatitis constitute the major risk involved in homologous transfusion since some 60,000 cases are reported each year in France. Prevention of transmission of disease by blood transfusion is based on decreasing homologous transfusions and especially by saving blood. Indeed, when surgery is planned, units of the patient's blood can be obtained in the weeks prior to it to be used during the operation or the immediate follow-up period. In case of emergency surgery, blood is collected preoperatively making it possible to obtain hemodilution during surgery and an autotransfusion if necessary at the conclusion of the procedure. Finally, there are methods to recover blood at the actual site of the surgical procedure.

Blood transfusion and hepatitis: still a threat?

The incidence of post-transfusion hepatitis (PTH) in recipients of blood products is reviewed. PTH was observed in 10%-12% of recipients of blood products in the United States, 2%-4% in northern Europe and 15%-20% in southern Europe. All studies indicate that 80%-90% of all PTH cases are attributed to non-A/non-B. At least 40% of the patients with PTH non-A/non-B will develop chronic hepatitis or cirrhosis. No specific tests for the detection of the non-A/non-B agent(s) exist. However, several independent studies indicate that part of the donors carrying the infectious non-A/non-B agent have increased levels of alanine amino transferase (ALT). When donors are excluded with elevated ALT values, it is estimated that about 30% of the PTH non-A/non-B cases would be prevented. Some studies indicate that anti-hepatitis B core (anti-HBc) positive donors may carry an increased risk to transmit the non-A/non-B agent, but more recent studies do not confirm this. There is hope that a specific non-A/non-B test will be developed soon.

Human immunodeficiency virus (HIV) infection in Jordan: a seroprevalence study.

Sera from 1124 Jordanian subjects were screened for HIV antibodies by enzyme immunoassay (EIA). The study population represented healthy rural and urban residents of Jordan as well as patients with hepatitis and their contacts, and patients with a variety of other diseases. Two patients with hepatitis had a positive test result by enzyme immunoassay and Western blot. Neither had AIDS-like illness and both probably acquired HIV infection abroad. There were no other positive serologic results for the population. False positive reactions by EIA can arise following repeated freezing and thawing of sera.

Peripheral blood remission of hairy cell leukemia after transfusion hepatitis.

Hairy cell leukemia is a chronic lymphoproliferative disorder characterized clinically by splenomegaly and cytopenias. Spontaneous remissions are rare and splenectomy is often performed when the blood counts worsen and cause symptoms. Three of our patients with hairy cell leukemia developed recurrent pancytopenia and transfusion-dependent anemia after splenectomy. Each subsequently acquired transfusion hepatitis and in two patients marked hematologic improvement was noted within 2 months. Complete peripheral blood remission occurred within 17 months in all patients although bone marrow infiltration with hairy cells persisted. One patient remains in remission for 12 years; the other two succumbed to infectious illnesses but with normal blood counts. The mechanism by which hepatitis virus induces hematologic recovery in patients with hairy cell leukemia is unknown but may involve augmentation of the interferon system.

Nonoperative observation therapy for splenic injuries: a safe therapeutic option?

Combining these reported and estimated incidences of mortality from overwhelming postsplenectomy infection, splenic salvage with nonoperative observation therapy and operative therapy, and the incidence of posttransfusion hepatitis and related mortality provides a conditional probability estimation of the risks of death with nonoperative observation therapy and operative therapy (Figure 4). The combined mortality rates for nonoperative observation and operative therapies are based on the following measured and estimated statistics: The post-transfusion hepatitis death rate per unit of blood transfused is 0.14 percent. Forty percent of children and 20 percent of adults who have successful nonoperative observation therapy receive an average of 2 units of blood. One hundred percent of children and adults in whom nonoperative observation therapy is unsuccessful receive an average of 4 units of blood. Twenty percent of children and adults who undergo operation initially receive an average of 2 units of blood. Ten percent of observed children require laparotomy and 75 percent of these patients then undergo splenectomy. Forty percent of adults who have nonoperative observation initially later require laparotomy, 93 percent of whom also require splenectomy. Ten percent of children and adults treated with initial operation later require splenectomy. Death from overwhelming postsplenectomy infection occurs in 0.026 percent of adults who undergo splenectomy and 0.052 percent of children who undergo splenectomy. Given these assumptions, the conditional probability of death in a child who initially undergoes nonoperative observation therapy is 0.17 percent compared with 0.06 percent for initial operative therapy. In adults, 0.26 percent of the observed patients die compared with 0.06 percent for those operated on initially. As stated, many of the percentages or probabilities listed are estimations based on the best available clinical data. The inability to establish a mortality rate from overwhelming postsplenectomy infection remotely resembling that reported for otherwise healthy patients required an unsubstantiated estimate. However, even when mortality rates from overwhelming postsplenectomy infection of 0.43 percent and 0.6 percent were substituted, early laparotomy still produced lower mortality rates. This continues to be true if one assumes that early laparotomy will result in 50 percent or even 100 percent of patients undergoing splenectomy, although in these cases the statistical differences would be less. We acknowledge that these statistics may exceed or underestimate the true risk of either treatment plan.(ABSTRACT TRUNCATED AT 400 WORDS)

A prospective study of cryoprecipitate administration: absence of evidence of virus infection.

In a prospective study of cryoprecipitate administration to patients who had never received large pool concentrates, no evidence of hepatitis or HIV infection was detected in a follow up period of one year. Following the introduction of screening of blood donors for anti-HIV in the UK in October 1985 the use of cryoprecipitate in selected cases should be reconsidered.

Hepatitis-free interval after clotting factor therapy in first infused haemophiliacs.

Post-infusion hepatitis is known to occur very frequently in haemophiliacs after treatment with unheated commercial clotting factor concentrates, obtained from large plasma donation pool. On the contrary, single-donor cryoprecipitate is likely to carry a lower risk of transmitting hepatitis. To evaluate this hypothesis, we retrospectively reviewed the medical records of 25 first infused haemophiliacs (from 1981 to 1984) treated with unheated commercial clotting factor concentrates (n = 19) or cryoprecipitate (n = 6). The hepatitis-free interval after the beginning of therapy was expressed as exposure days. The end point of each patient, i.e. the hepatitis occurrence, was defined as an increase of amino-transferases (ALT and AST) and/or the seroconversion of HBV-markers, which were checked every three months. The life-table method and log-rank test showed that cryoprecipitates had a significantly longer hepatitis-free interval (p = 0.0131, log-rank test) and a lower risk of transmitting hepatitis (p = 0.01-0.05, life-table method) than the commercial concentrates. However, the safety of cryoprecipitate therapy was shown to cover only a few exposure days, and so the real advantage of this product depends on the bleeding frequency of the patient concerned. We believe that these methods and our findings may be useful to assess and compare the safety of the new "heat-treated" clotting factor concentrates.