India has the third largest HIV infected population; 2.09 million
as of 2011 [1]. Voluntary counselling and testing is a key element in
comprehensive prevention [2]. Advances in HIV therapeutics have
highlighted the importance of expanded testing [3]. The availability
of a simple non-invasive reliable alternative to blood should
increase access to HIV testing (and therefore to counselling and
therapeutics) across a wide spectrum of the population [4].
Detection of anti-HIV antibodies is the mainstay of HIV infection
diagnosis [5]. Prevalent techniques utilising serum require at least one
or all of the following: access to the testing facility, trained personnel
for sample collection and processing and sophisticated electric
equipment [6]. Unfortunately, these facilities may not be readily
available everywhere. There is therefore an urgent need for ease of
procedure and rapid results. This requires a sample which is easy to
collect, process and safe to use. Saliva fits this profile admirably.
A salivary sample eliminates occupational risks associated
with needle-stick accidents and injuries from broken glass
collection vials [7]. Salivary transmission of HIV infection has
been proven to be virtually non-existent [8]. This makes saliva
samples more readily disposable, which is important in resource
limited settings, where incineration or autoclaving may be
unavailable [9]. Saliva collection is non-invasive and painless,
thereby increasing patient comfort, acceptability of the method,
and compliance with repeated testing. Finally, the likelihood of
obtaining an adequate saliva sample is high whereas adequate
amounts of blood are sometimes difficult to obtain due to cultural
or religious reasons, poor venous access, or lack of adequate
collection and storage systems [10]. The advantages of saliva can
be realised when it is used in simple but reliable non-laboratory
assays.
With this background, saliva based rapid HIV testing seemed an
attractive proposal for the Indian scenario. The study was approved
by the ethical committee of the Government Dental College,
Mumbai, India