Infectious Diseases

In 2012, BC became the first province in Canada to implement a province-wide condition-of-service influenza prevention policy (henceforth “the policy”), including the requirement that health care workers either receive the seasonal influenza vaccine or wear a mask while in patient care areas for the duration of the influenza season. A research team that includes representation from the five regional Health Authorities, the BC Centre for Disease Control, Providence Health Care) and the Provincial Health Services Authority will evaluate the effectiveness of the policy in BC.

Hepatitis C (HCV) remains a significant challenge that affects an estimated 60,000 British Columbians. Many more, in particular, people who inject drugs (PWID), remain highly vulnerable to HCV infection. Recently, there have been dramatic developments in the treatment of HCV with the arrival of direct acting antivirals (DAAs). These drug regimens are highly effective, offering vastly superior cure rates over past HCV treatments.

In 2014, mobile phone subscriptions will outnumber the world’s population. Expanded mobile phone use presents a tremendous opportunity to engage patients in care, particularly those in remote or isolated situations.

Our immune system is our chief defense against infection, but it is a double-edged sword. Inappropriate or over-exuberant immune responses can be harmful or even fatal. The optimal response is one that is strong enough to clear the pathogen but not so strong that it also kills the host.  Dr. Perona-Wright is working to understand how this balance is achieved by studying a family of signalling molecules known as cytokines, soluble messengers used by cells of the immune system to communicate with one another.

The ability of bacterial pathogens to invade and survive within the cells of a human host is governed by the interplay between host and bacterial factors. Under these conditions, both host and pathogen generate multiple mediators that, through interactions with other proteinous factors alter the intercellular host environment. These interactions govern the development of disease and are largely mediated by the physical association of proteins and the generation of protein complexes.

With an estimated 1.5 million fatal cases among children and about 2 billion cases total annually, diarrheal diseases are a significant cause for morbidity and mortality worldwide. Enteropathogenic and enterohemorrhagic E. coli (EPEC/EHEC) are two forms of diarrheagenic E. coli that cause these diseases. EPEC provokes potentially fatal infantile diarrhea and EHEC triggers severe diarrhea, which can progress to fatal renal failure. Both pathogens infect epithelial cells of the host intestine.

The development of resistance to commonly used antiviral drugs Relenza and Tamiflu has become a serious problem facing the world. It is reported that 98 percent of influenza A/H1N1 strains in North America are resistant to Tamiflu. The Withers group has designed a series of sialic acid analogs in which the C-2 OH group was replaced with fluoride to trap the virus by the formation of a covalent intermediate.

Although traditional HIV prevention strategies — behaviour modification, condoms, needle exchange – have been very successful, their effect has reached a plateau since they are not always available, practical, or fully adhered to. In the past five years, research has shown that using antiretroviral therapy (ART) to treat those infected with HIV not only decreases mortality and morbidity but also decreases HIV transmission. Unfortunately, many individuals are still unaware that they are HIV-positive or that they should be on ART, since they have not been linked to our health-care system.

Access to antiretroviral therapy (ART) for HIV infection has dramatically increased in recent years. More than eight million people worldwide are now being treated, the majority of whom reside in sub-Saharan Africa. The success of ART roll-out has been possible through large increases in funding, but has been facilitated by the promotion of the “public health approach” to implementing ART in resource-limited settings.

Millions of newborns and infants die each year from infectious diseases. Many of these deaths are preventable, and analysis of the immune development of children can help define paths for medical intervention that may save lives.

HIV has tremendous capacity to mutate and evolve due to the body’s immune response. However, the extent to which the virus has adapted to its human hosts over the course of the pandemic remains poorly understood. Repeated cycles of immune selection and transmission may allow the accumulation of key “escape mutations” — changes in the viral genome that help HIV evade the body’s defences.

Existing viral vaccines provide immunity against a number of important infectious diseases. The technologies used to develop these vaccines generally work best against viruses that do not mutate very much in nature. However, conventional vaccine design approaches have proven inadequate for viruses such as HIV-1 that continuously evolve in order to evade our immune defenses. Thus, new vaccine design strategies are needed to tackle viruses like HIV.

Each year the influenza virus infects approximately 10% of the human population, resulting in hundreds of thousands of deaths. Even in North America, nearly 40,000 annual “excess deaths” are attributed to influenza or to secondary bacterial infections. Despite a World Health Organization-monitored vaccine program, the disease remains a significant global health issue, requiring the use of antiviral drugs like oseltamivir (Tamiflu). A significant problem in controlling the spread of influenza is the emergence of oseltamivir-resistant strains.

Pre-term babies, those born before week 37 weeks of gestation, are more susceptible to invasive infections than full-term babies. The smallest babies born “extremely” premature (those born before 32 weeks, or approximately 1,500 grams or less of birth weight) suffer the greatest burden of infection among all age patient age groups in BC and other developed countries in general. About one in four “extremely” pre-term babies suffers from an invasive infection, which adds up to more than 8,760 new invasive infections in North America each year.