The return of brucellosis

Brucellosis, also known under the names of Undulant fever, Mediterranean fever and Malta fever is closely linked with Malta’s medical history and for long endemic to our Islands. Every reported case was investigated by the medical officers of health who contacted the head of each affected household for an epidemiological enquiry including a food history. All these cases were associated with the consumption of fresh cheeselets made from unpasteurised milk. During the investigation some 900 kgs of cheeselets from 27 producers, 12 wholesalers and 384 retailers were seized and tested.peer-reviewe

Surveillance of Hepatitis B in Malta : a four year trend

Surveillance systems include three fundamental elements of ongoing collection, analysis and feedback or dissemination of the data. A surveillance system for Hepatitis B was established in 1988 in order to improve prevention and control of transmission of this endemic disease. A disease register including data obtained mainly from notifications, laboratory reports and active case finding was established. This paper shows the findings from 1990 to 1993. The system shown cannot claim to be complete. However the findings suggest that some 14 clinically evident cases of Hepatitis B are confirmed each year. No rising trend has been seen. In anyone year a prevalence of 15.4 x 10-5 HBsAg positive results in persons who had previously not known that they were positive may be detected. Six month follow-up of these persons reveals that some 39 persons become chronic carriers each year. This has implications both for the targeted vaccination programme as well as for the individual’s chronic liver complications and treatment.peer-reviewe

Epidemiology of AIDS in Malta

The occurrence, frequency, distribution and determinants of HIV and AIDS are described for Maltese residents. Up to 30 June 1996, 38 notifications of AIDS were received by the Public Health Department (36 in males), 35 died. The overall mean survival between notification date and death was calculated using data for 28 reported cases as 216.71 days. Mean age at notification was 30.5 years (range: 2 to 48; median 31). Occurrence in males was highest for homosexuals/bisexuals (52.8%), followed by recipients of contaminated blood products (30.6 %) and heterosexual contact (5.6%). The two females acquired HIV through mother-to-child transmission (abroad) and heterosexual intercourse respectively. Mode of transmission was unrecognised in 7.9% of cases. Epidemiological data on AIDS cases usually reflects the situation of HIV transmission some twelve to fifteen years previously. Sero-surveillance studies are now indicated to clarify the actual prevalence of HIV infection.peer-reviewe

A cross-sectional survey of a dermatology outpatient service in Malta

A survey of the outpatient service provided by a consultant dermatologist at the national dermatology department in Malta was carried out. The aims of this study were to identify the main conditions being treated and to analyze management and referral practices. Possible implications for future training of primary care physicians were also investigated. The survey was carried out for one week every season over a 12-month period, giving a total study period of four weeks. Data was collected on a total of 662 patients (401 new patients and 261 follow-ups). The average waiting time for a routine clinic appointment for new cases was 4 weeks, but 18% of patients were seen within 48 hours of referral and 7% were seen within one week. Age-specific attendance rates were highest for females over 50 years and males over 60. Overall, the commonest conditions seen were chronic leg ulcers, psoriasis, skin infections and seborrhoeic keratoses. Skin biopsy was the most frequent investigation performed and topical treatment was the commonest form of therapy. Private general practitioners and government doctors based in health centres accounted for 51% and 29% of all referrals respectively. A diagnosis was offered in 65% of referral notes. Of these, 44% had a diagnosis matching that given by the dermatologist at the patient's first visit. Treatment was attempted prior to referral in 64% of patients with acne but in only 15% of patients with viral warts.peer-reviewe

Infectious intestinal disease : do we know it all?

Infectious intestinal disease (IID), with associated high morbidity and considerable mortality worldwide, causes a wide spectrum of illness. This ranges from mild discomfort to illness with severe complications. The economic burden from direct and indirect costs may be high. It is acquired by oral ingestion of micro-organisms which are transmitted from person to person; via food or water or through contact with animals or contaminated objects. Viruses are the commonest cause in developed countries. In Malta, medical practitioners and laboratories are the main source of data on IID. However, under-reporting is a problem. In order to fill in the lacunae in information on the disease burden, population-based-studies are required. Along with other countries, Malta has embarked on a number of studies to describe and quantify under-reporting of IID. This may assist in strengthening the surveillance system which, in combination with other measures, should result in an improvement of the control of IID.peer-reviewe

Trends in sun exposure awareness and protection practices in Malta : 1999-2004

Rising skin cancer incidence rates have led to sun awareness campaigns in Malta since the early 1990s. The aim of this study is to assess the impact of these campaigns by analysing trends in sun exposure-related knowledge and behaviour amongst the Maltese people. A total of 559 Maltese pedestrians aged 16-50 years were interviewed in 1999. The same questionnaire was used to interview 304 pedestrians in 2004. More people admitted spending leisure time outdoors during peak sunshine hours in 2004 than in 1999 (85.9% vs 62.4%, p<0.001). There was a drop in people regularly wearing a hat during outdoor leisure activities from 32.4% to 18.4% (p<0.001), and from 37.5% to 9.3% (p<0.001) during outdoor work activities. Rates of regular sunscreen use remained constant at about 50% using it for outdoor leisure activities, but dropped from 25.0% to 9.3% for outdoor work (p=0.02). In 2004, 96.1% of participants having children aged less than 12 years stated that they regularly used sunscreen on their children (87.0% in 1999, p=0.01), while 66.2% said that their children regularly wore a hat (78.4% in 1999, p=0.05). More people were regarding a suntan as unhealthy in 2004 than in 1999 (62.8% versus 37.0%, p<0.001). The mass media remained the most important source of health information.peer-reviewe

Laboratory surveillance of communicable diseases : enteric pathogens

Laboratories represent a crucial link in the surveillance chain. Since only a small proportion of cases of enteric infections are asked to submit a stool sample, one needs to assess the practices for testing for enteric pathogens and their notification practices. Five local laboratories participated in this study. This included a description of the laboratory practices; capacity for stool sample analysis; awareness of the notification system and the factors which could improve the system at laboratory level.peer-reviewe

Tree-mediated methane emissions from tropical and temperate peatlands

Methane production and transport processes in peatlands are fairly well understood, but growing evidence for emission of methane through trees has highlighted the need to revisit methane transport processes. In wetland trees, morphological adaptations such as development of hypertrophied lenticels, aerenchyma and adventitious roots in response to soil anoxia mediates gas transport, transporting both oxygen from the atmosphere to oxygen-deprived roots and soil-produced methane from the root-zone to the atmosphere. Although, tree-mediated methane emissions from temperate tree species have been confirmed, methane emissions from tropical tree species and processes that control tree-mediated methane emissions remain unclear. This study explains the role of trees in transporting soil-produced methane to the atmosphere and uncovers the principal mechanisms of tree-mediated methane emissions. Methane emissions from eight tropical tree species and two temperate tree species were studied in situ. The mechanisms and controls on tree-mediated methane emissions were investigated using three year old common alder (Alnus glutinosa; 50 trees) grown under two artificially controlled water-table positions. Methane fluxes from whole mesocosms, the soil surface and tree stems were measured using static closed chambers. Both temperate and tropical tree species released significant quantities of methane, with tropical trees dominating ecosystem level methane fluxes. In temperate peatlands, both the methane gas transport mechanism and quantity of methane emitted from stems is tree-species dependent. In Alnus glutinosa, no correlations were observed between stomatal behaviour and tree-mediated methane emissions, however, stem methane emissions were positively correlated with both stem lenticel density and dissolved soil methane concentration. In Alnus glutinosa, no emissions were observed from leaf surfaces. The results demonstrate that exclusion of tree-mediated methane emissions from flux measurement campaigns in forested peatlands will lead to an underestimation of ecosystem-wide methane emissions

Faunistic diversity of Maltese pocket sandy and shingle beaches : are these of conservation value?

The littoral fauna of Maltese sandy and shingle beaches is generally regarded as impoverished and consequently of little conservation interest. The fauna of three sandy and three shingle beaches was systematically sampled by coring, standardised searching and pitfall traps. Diversity and population density were highest at the surface for sandy beaches, but were highest below the surface for shingle. The two beach types had distinct suites of species and individual beaches were faunistically distinct. Maltese sandy and shingle beaches are of conservation importance for their habitat-restricted species, some of which have limited local and regional distributions, and are internationally protected.peer-reviewe

Runtime monitoring of distributed systems

Distributed and component-based architectures are becoming more prevalent computer systems. The increased complexities introduced by the distribution hampers dependability, emphasising the need for verification techniques tailored for a distributed setting. Runtime verification has proven to be a viable approach for verifying correctness, by focussing on the adherence of the runtime-generated trace to the desired properties. We present a broad taxonomy of current techniques to distributed monitoring, culminating in the proposal of a novel migrating monitor approach. We argue for certain situations where this approach presents clear advantages over current techniques.peer-reviewe