Vaccines are an indispensable weapon in the battle to prevent disease, both in humans and animals. Provision and protection of the vaccine supply is so essential that no possible pathogen is beyond suspicion. So it is with nanobacteria (NB), a potential infectious agent so new that science is still debating its existence as a "living organism". We analysed 6 veterinary vaccines and 3 inactivated human polio vaccines produced in cell culture for NB. We report that 3 of 6 European veterinary vaccines contained NB. Of the 3 distinct lots of polio vaccine from European manufacturers, 2 lots from manufacturer-1 were NB-positive and 1 lot from manufacturer-2 was NB-negative. These results suggest that not all lots of vaccine contain detectable NB. The public health risk, if any, from nanobacteria is yet to be defined, but nanobacteria have been found in kidney stones, liver and kidney cyst fluids, and implicated in kidney stone formation.

In the early 1990’s, Drs. Olavi Kajander and Neva Ciftcioglu, University of Kuopio, Finland discovered a minute self replicating agent, which was named "nanobacteria", in fetal bovine serum (FBS) that mediates mineral (calcium phosphate) formation under conditions found in blood and urine. NB was subsequently found to contaminate cell cultures widely used in research and to pass through filters commonly used to sterilize vaccines. Several vaccines are produced in mammalian cell cultures that were initially or are currently cultured in media supplemented with FBS. Thus, the question arose, "Could the NB found in some batches of FBS contaminate some vaccines"?

To detect nanobacteria in these 9 vaccines, the Kuopio University team cultured the vaccines in routine tissue culture medium known by prior testing to be free of NB and examined the original vaccines and cultured vaccines by electron microscopy, and immunologic tests for NB antigens (immunofluorescent staining, dot blot assay and ELISA). NB were found 3 of 6 vet vaccine products and 2 of 3 human vaccine products prepared using FBS. A second question arose, "Even if NB are present in the culture broth, why were they not removed during the purification and sterilizing steps of vaccine production"?

Cell culture mediated viral vaccine production requires the use of cells to propagate large amounts of virus, which is then filtered to remove contaminates and cells present in the propagation step. The viruses passing through the filters are then further processed and inactivated prior to use. NB are in the same size range as certain large viruses, and may adhere to viruses thus escaping purification steps using filtration. NB are also resistant to many disinfecting chemicals and antibiotics. NB can exist intracellularly and grow in the absence of FBS. At this time it is not known if FBS added to the production cell lines or NB in the cells lines themselves are the source of NB contamination in these cases.

The Center for Biologics Evaluation and Research (CBER) and the U.S. Food and Drug Administration (FDA) learned earlier this year that some vaccines were manufactured with bovine–derived materials obtained from countries where bovine spongiform encephalopathy (BSE; mad cow disease) is prevalent or where a substantial risk for BSE exists. Creutzfeldt-Jakob disease (vCJD), the human equivalent of BSE, has been attributed to, among other possibilities, eating beef products from cattle infected with the prion agent of BSE. Although there is no evidence to date that cases of vCJD are related to the use of vaccines, interestingly a vaccine lot was withdrawn because of being exposed to FBS from the country where high risk for this prion disease exists.

The study summarised in the first paragraph will be presented in the 101^st ASM Meeting in Orlando in May 21, 2001 (1.00-2.30pm). The Kuopio team’s message to the scientific society in this presentation will be: More research is needed to understand nanobacteria and their role in human and animal diseases. To err on the side of safety is no vice; just as prions and viruses were viewed with scepticism before they were completely characterised, so concepts of nanobacteria (and the scientists who study them) will be knocked around until more is known about NB. Vaccines should be regarded as safe and essential to human health in the modern age until they are proven otherwise.

Related Literature:

NB have been linked to kidney stones (Ciftcioglu et al., Kidney International 56:1893-8,1999),

as a kidney stone causative agent (Garcia Cuerpo et al., Arch Esp Urol 53:291-303, 2000), and

in polycystic kidney disease (Hjelle et al, Kidney International 57: 2360-2374, 2000).

For a recent review of nanobacteria, (Kajander, Ciftcioglu, Miller-Hjelle, Hjelle. Current Opinions in Nephrology and Hypertension 2001 in press).