The first postmodern pandemic: 25 years of HIV/ AIDS.

Science responded to the challenge of AIDS by rapidly identifying aetiology, describing pathogenesis and transmission routes, and developing diagnostic tests and treatment. However, this did not prevent the global spread of HIV, with 25 million fatal cases so far, another 33 million infected, and disastrous socioeconomic and demographic consequences. In spite of unprecedented political attention and financial resources, the response is falling further behind the growth of the epidemic. This is partly due to the unique characteristics of the virus, such as persistent infection, vertical transmission and a variability that allows it to escape immunity and antiretroviral drugs, and partly due to human characteristics such as a strong procreative instinct, drug use and ostracism. Denial, myths and complacency are major obstacles to rational measures. With no cure or vaccine in sight, scaling up prevention is of paramount importance. To meet the goal of universal access to prevention, treatment and care by 2010 would require a quadrupling of funding to an estimated US$42 billion by 2010, including adequate overall strengthening of healthcare systems, but in any case, the world will have to learn to live with HIV for the foreseeable future.

HIV infection in the nineties.

By the year 2000 a cumulative global total of 30-40 million men, women and children are projected to have been infected with HIV. This will represent a three to four times increase of the present total. Currently, it is estimated that about 5000 persons are newly infected daily. Worldwide, the predominant and increasing mode of transmission is by heterosexual intercourse. Therefore, the number of infected women will equal that of men. Consequently, more infants will be infected by their mothers and more infants will be orphaned as their parents die of AIDS. By the end of the 1990s, over one million adult AIDS cases and deaths per year are expected, most of them in developing countries. Although the majority of HIV infections are currently occurring in sub-Saharan Africa, the annual number of HIV infections in Asia is projected to exceed that in Africa during the 1990s. Also, in industrialized countries, the proportion of heterosexual transmission is increasing, and AIDS is becoming one of the predominant causes of death in young men and women. In spite of promising scientific progress, vaccines and therapeutic drugs are not expected to have any major impact on the global development of the pandemic during the 1990s. WHO is promoting behavioural changes, condom use and control of other sexually transmitted diseases as the most important preventive measures.

The clinical significance of bacterial growth in venous leg ulcers.

The importance of pathogenic bacteria in venous leg ulcers was analysed in a randomized open trial divided into 2 parts. During the first 2-week period the effects of physiological saline and dextranomer beads were compared. During the following 8 weeks the effect of porcine skin, aluminium foil and a double layer bandage were compared. The assessment of the results of treatment was based on the area and volume of the ulcer measured by stereophotogrammetry and the bacteriological findings. Staphylococcus aureus was the commonest isolated species. Mixed cultures comprising Staph. aureus and gram-negative bacteria were the next commonest finding. There was a low frequency of isolation of anaerobic bacteria. The bacteriological findings were similar in the different treatment groups. The nature of the bacterial isolates and the colonization estimated by a contact-transfer procedure bore no relationship to the clinical assessment as to whether the ulcer was clean or purulent. Healing of the ulcer was not influenced by the bacteria present. The findings seem to indicate that as a rule the bacteria in the ulcers are saprophytic and will disappear when the favourable environment for their growth is lost.

Epidemiological patterns in legionellosis in Sweden.

Since 1976, 173 confirmed cases of legionellosis of the pneumonic type have been reported in Sweden. Sixty-eight cases belonged to a community-acquired outbreak in the summer and fall of 1979. Fourty percent of the sporadic cases are travel-associated. Half of them had visited Mediterranean countries. As much as 76% of the sporadic cases were men, 23% men of the age groups 15--54 years. There is an ongoing nosocomial outbreak in a renal transplant unit. L. pneumophila belonging to serogroups 1, 3, 5 and 6 have been isolated from patients or environment (e.g. from the cooling tower of a shopping mall in connection with the community-acquired outbreak and tap water in the nosocomial outbreak). A few cases of L. micdadei and L. bozemanii infections have been diagnosed. The proportion of legionellosis among all community-acquired pneumonia patients in a prospective study was only 1.8%. The frequency of antibodies to L. pneumophila among blood donors in non-endemic areas ranged between 0--6% compared to 20--21% in areas where outbreaks have occurred. The fatality rate has been low and the clinical outcome satisfactory even in cases without adequate antibiotic treatment.

Bacteriological aspects of infections of the upper respiratory tract.

In this introductory presentation, the bacteriology of acute otitis media, sinusitis and orofacial infections is surveyed, and recent data on antibiotic resistance of the most common pathogenic bacteria are reported. In addition, the difference in the immunogenic effect of capsular polysaccharides from pneumococci and Haemophilus influenzae in children of different ages is mentioned. In acute otitis media and sinusitis, pneumococci and H. influenzae are the most common isolates followed in frequency by Branhamella catarrhalis and streptococci group A. It should be emphasized that the average relative risk of otitis media with effusion is much higher in children with viral respiratory infections than in children with nasopharyngeal colonization with pneumococci or H. influenzae. Anaerobic bacteria are the most common causes of odontogenic infections. Penicillin remains the most active of the currently available antibiotics against streptococci group A. Resistance to penicillin of clinical isolates has still not been documented, although resistance may occur to erythromycin and tetracycline. In pneumococci isolates obtained in Sweden, a relative resistance to penicillin occurs in a low percentage. They may also be resistant to erythromycin and tetracycline. The frequency of beta-lactamase producing H. influenzae has been followed nation-wide in Sweden during recent years. The mean frequency varies around 3-4% with local and seasonal peaks up to 12%. The majority of the H. influenzae isolates in Sweden are not fully sensitive to erythromycin, but resistance to chloramphenicol occurs. Most strains (including beta-lactamase producing) are sensitive to co-trimoxazole, cefuroxime, cefotaxime, cefotriaxone and cefaclor. Over 40% of clinical isolates of B. catarrhalis in Sweden produce beta-lactamase.(ABSTRACT TRUNCATED AT 250 WORDS)