Do Water Filters Remove Bacteria and Viruses? 6 Best Filters for 2024 and Why They're Worth It

Do Water Filters Remove Bacteria and Viruses? 6 Best Filters for 2024 and Why They're Worth It
What would you see if you were to look through a clear glass filled with water from your tap? Probably nothing but a clear liquid hopefully; or maybe it's white due some air bubbles. This water might look pretty clean and ready to drink. However, if your water is not adequately filtered or purified, even the clearest of water could contain bacteria or other contaminants that are invisible to the naked eye. Bacteria and viruses are microorganisms that can cause health problems and disease. Unfortunately, bacteria and viruses can end up in the water you use or drink and this poses significant health risks. Viruses and bacteria in water are more common in well water than they are in water coming from a municipal source. However, even though municipal water providers may disinfect water, there could be bacteria and viruses lurking in the pipes or storage tanks. Needless to say, it's important to ensure you have adequate filtration to protect your household from viruses and bacteria in water and unfortunately not all filters will do the job. Jump to:

Bacteria in water

Bacteria, viruses, and parasites are an invisible danger - they are not detected by the naked eye, and you can't necessarily smell or taste them either. You may not even know they're in your water. The only way to know if a water supply contains bacteria is to have it tested. Keep in mind that unfortunately it's just not practical to test water for every disease-causing microorganism. The easiest and most common way is to test for a group of indicator bacteria called total coliform bacteria. The best way to protect yourself from bacteria in water is with a proper filtration system that removes bacteria, viruses, and cysts. Microorganisms that may be found in water include:
  • Bacteria - Coliforms, E. coli, Shigella, Vibrio, Salmonella, Legionella, Enterococci
  • Enteroviruses - polioviruses, echoviruses, coxsackieviruses
  • Viruses - Norwalk virus, Rotaviruses
  • Protozoans / Parasites - Entamoeba, Giardia, and Cryptosporidium

    Giardia and Cryptosporidium are the most common cause of waterborne illnesses in the United States due to its resistance to disinfection. Even if you have a "strong stomach" or healthy immune system, it's not enough to protect you from the hazards that bacteria in water may cause you. Unfiltered water can be very harmful for those on medication, pregnant mothers, the elderly, and children. Their immune systems in particular are not strong enough to fight these dangerous microorganisms.

    Is there bacteria in municipal water?

    Public water suppliers are required by the Environmental Protection Agency (EPA) to regularly test for coliform bacteria. How often they test though depends on the supplier and size of the population served. They are required to notify the public if the water supply doesn't meet the EPA standards. You can obtain bacteria test results from your supplier. Keep in mind, even though they test for some bacteria is does not guarantee that that bacteria or other types of bacteria will not end up in the supply at some point. Unless testing occurs 100% of the time, it's impossible to know what's in the water all the time. Municipal water providers typically disinfect water with chlorine which kills most waterborne pathogens including those that can cause typhoid fever, dysentery, cholera and Legionnaires' disease. Chlorine is effective, cheap, and little effort is required; it's no wonder why chlorine is so widely used by municipal water providers. It's also an outdated way to treat water though - municipal water providers can and should do better. There's a distinctive taste and odor of chlorine in water that most people find unpleasant. Tasting or smelling chlorine in your water though is an indication that your water supply is being adequately treated for microorganisms. Even though chlorine kills most waterborne pathogens, chlorinated water carries dangers of its own. Chlorine in water causes heavy metals, like lead, to leach into the water when it makes contact with aging alloy pipes (a lot of homes have this type of plumbing). Drinking chlorine isn’t the only concern though: there is also the risk of inhaling the chloroform gas that’s created in the steam vapor during a shower with chlorinated water. Despite the widespread use of chlorine, some parasites like cysts, Giardia, and Cryptosporidium can be resistant to disinfection. If you get your water from a municipal source, it's highly recommended that you have a filter capable of reducing chlorine along with other contaminants including bacteria, viruses, and cysts from the water. Carbon filtration is most effective at reducing chlorine; and absolute charged nanofiber filters or ultrafiltration removes bacteria.

    Is there bacteria in well water?

    The only way to know for sure is to have the water tested for microorganisms. There is no requirement to have private wells, springs, or other sources tested for bacteria - it is up to the individual owner. You can read more about well water testing here. At minimum, you should test for total coliform bacteria. Total coliform bacteria do not usually show up a few feet into the soil. If they show up in a water test, it suggests a surface contamination has gotten into the water and that disease-causing microorganisms may be present. Disinfection kills coliform bacteria and most disease-causing microorganisms. In addition to bacteria, well water is susceptible to other issues. It's strongly recommended to have adequate water filtration for any water your drink or use from a well, spring, or other source. Just because water may test "safe," it doesn't mean the water has always been or will continue to be safe.

    Types of water filters for bacteria and viruses

    The two most common types of water filters are:
    • Whole house water filters. This water filter is installed into your main water line so that all the water that enters your house has been filtered
    • Under sink water filters. An under sink water filter filters the water that comes out of that specific tap. This type of filter may also be called a point of use water filter.
    Both these style of water filtration systems can potentially remove bacteria and viruses from water, however it depends on what filter cartridge or filtration technology is present in the system. Not all filtration systems are created equal, nor do all filters remove bacteria and viruses.

    Water filters for bacteria and viruses

    • Ultrafiltration removes bacteria and viruses. Ultrafiltration membrane technology is the latest and greatest in water purification for removing bacteria and viruses. It purifies and disinfects water to produce great-tasting water that is safe to use and drink. Ultrafiltration removes over 99.9% of bacteria, viruses, and giardia & cryptosporidium. It’s innovative technology lets you flush (clean) the membrane whenever it gets full of contaminants.
    • Absolute charged nanofiber filters remove bacteria and viruses. The "charged" high zeta potential attracts ultrafine contaminants like pathogenic bacteria and cysts; the small micron / submicron rating (0.2) means it removes all contaminants that small and larger. Pathogenic removal rate is more than 99.99% of viruses and bacteria, and more than 99.95% of cysts.
    • Ultraviolet (UV) or ozone purification kills bacteria, but it doesn’t remove bacteria from the water. That means that bacterial remnants are still present in your water. Plus, it requires a lot of electricity.
    • Reverse osmosis can remove bacteria, but it's imperfect. Reverse osmosis systems are very, very rarely "certified" to remove bacteria. Check the manufacturer has the documentation to back up the RO system is in fact certified to remove bacteria. As a process reverse osmosis does remove bacteria since it can't pass through the reverse osmosis membrane due to size. However, membranes can have defects which allow the bacteria to pass through. Sometimes bacteria will even move around the o-ring seals in reverse osmosis systems. There's also the possibility that bacteria can move up the pure water stream and attach to the RO membrane. So reverse osmosis systems can remove bacteria, but systems are rarely certified to actually do so.

    The 6 best bacteria water filters that remove bacteria and viruses (and why they're worth buying!)

     

    Best Whole House Water Filters for Removing Bacteria and Viruses

    PS-1000 Ultrafiltration System

    The best whole house water filter for bacteria and viruses is the PS-1000 ultrafiltration membrane filter. Or, if you have lead or lots of sediment or chemicals in the water, please see other systems below.

    The Premiere PS-1000 ultrafiltration systems removes bacteria, viruses, and giardia & cryptosporidium from your water. It has a continuous, 8 gallon per minute flow rate which is perfect for most homes. If you need a higher flow rate, you can "stack" these systems. Ultrafiltration technology does not require a storage tank or electricity to operate. One of the best features of ultrafiltration and why this system is worth buying is that you can easily clean the membrane: simply turn a valve to flush it. This cleanable membrane saves money in the long-run because it lasts 3 - 5 years (or more). There's also no drop in water quality. With other filter systems, there’s no option to turn a valve to clean the filter – it means you have to buy a new replacement water filter. Don't waste time and money changing filters every year, six months, or more with other filter systems. You'll know it’s time to flush the PS-1000 membrane when there is a drop in water pressure coming from the system.

    Why the PS-1000 is one of the best bacteria water filters and worth buying: Has an easy to flush membrane filter that lasts 3 - 5 years (or more). Other technology which removes ultrafine contaminants can't compete with this filter life. In the long-run, you'll save money by not having to replace filters as often.

    PS-2000PB Ultrafiltration System with Catalytic Carbon Filter

    The Premiere PS-2000PB is a two stage water filter system that has the same ultrafiltration membrane as the PS-1000 (mentioned above) plus a special carbon post-filter for lead. The carbon post-filter reduces both types of lead (soluble and particulate), chlorine, chloramine, VOCs, perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and more. Like the PS-1000 and other PS-2000 series systems, the PS-2000PB ultrafiltration system removes bacteria, viruses , and giardia & cryptosporidium from your water. It has a continuous, 8 gallon per minute flow rate. No storage tank or electricity required. One of the best features of ultrafiltration is that you can easily clean the membrane: simply turn a valve to flush it. Being able to flush (clean) the membrane saves money in the long-run because it lasts 3 - 5 years (or more). There's also no drop in water quality either. With other filter systems, you have to keep buying replacement water filters because you can't clean them like you can the ultrafiltration membrane. You'll know it’s time to flush the ultrafiltration membrane when there is a drop in water pressure coming from the system. The special carbon post-filter (BG-20PB) should be replaced annually. This special post-filter reduces both types of lead (soluble and particulate) and other chemicals that due to their liquid nature / chemical structure, cannot be removed by ultrafiltration membrane alone. Activated coconut shell carbon block is highly effective at adsorbing chemicals such as chlorine, chloramine, PFOA, PFOS, THMs (trihalomethanes), VOCs (volatile organic chemicals), MTBE (methane tertiary butyl ether), and more.

    Why the PS-2000PB is one of the best bacteria water filters and worth buying: This mighty system protects your household from both types of lead (soluble and particulate), bacteria, viruses, cysts, parasites, chlorine, chloramine, PFOA/PFOS, and more. It has an easy to flush membrane filter that lasts 3 - 5 years (or more). Other technology which removes ultrafine contaminants can't compete with this membrane life. The Aquasana OptimH2o + UV filter is the closest competition and the PS-2000PB beats it on filtration, features, and especially price: the PS-2000PB system is significantly less. In the long-run, you'll save money by not having to replace filters as often - 5 years of replacement filters on our system cost much less than the Aquasana OptimH2o + UV filter.

    PS-2000S Ultrafiltration System with Sediment pre-filter

    The Premiere PS-2000S is a two stage water filter system that has a sediment pre-filter and the same ultrafiltration membrane as the PS-1000 mentioned above. The sediment pre-filter removes sediment, dirt, rust, and other particles in your water that can clog up the ultrafiltration membrane and shorten the life-span of the purifier. Like the PS-1000, the PS-2000S ultrafiltration system removes bacteria (over 99.9999%), viruses (over 99.99%), and giardia & cryptosporidium (over 99.95%) from your water. It has a continuous, 8 gallon per minute flow rate. No storage tank or electricity required. One of the best features of ultrafiltration is that you can easily clean the membrane: just turn a valve to flush it, very easy. Being able to flush (clean) the membrane saves money in the long-run because it lasts 3 - 5 years (or more). There's also no drop in water quality either. With other filter systems, you have to keep buying replacement water filters because you can't clean them like you can the ultrafiltration membrane. You'll know it’s time to flush the ultrafiltration membrane when there is a drop in water pressure coming from the system. The sediment pre-filter (BG-20SED) will need to be replaced annually. This pre-filter is the workhorse of the system taking the brunt of the water issues (sediment). The sediment pre-filter protects the ultrafiltration membrane from being unnecessarily clogged and ensures it has a full life-span.

    Why the PS-2000S is one of the best bacteria water filters and worth buying: If you have lots of sediment in your water, this system tackles sediment before it can clog the ultrafiltration membrane prematurely. It has an easy to flush membrane filter that lasts 3 - 5 years (or more). Other technology which removes ultrafine contaminants can't compete with this membrane life. In the long-run, you'll save money by not having to replace filters as often.

    PS-2000C Ultrafiltration System with Anti-Scale Carbon Filter

    The Premiere PS-2000C is a two stage water filter system that has the same ultrafiltration membrane as the PS-1000 (mentioned above) plus a carbon post-filter. The carbon post-filter removes chlorine, chloramine, THMs (trihalomethanes), VOCs (volatile organic chemicals), MTBE (methane tertiary butyl ether), and more. Like the PS-1000, the PS-2000C ultrafiltration system removes bacteria (over 99.9999%), viruses (over 99.99%), and giardia & cryptosporidium (over 99.95%) from your water. It has a continuous, 8 gallon per minute flow rate. No storage tank or electricity required. One of the best features of ultrafiltration is that you can easily clean the membrane: simply turn a valve to flush it. Being able to flush (clean) the membrane saves money in the long-run because it lasts 3 - 5 years (or more). There's also no drop in water quality either. With other filter systems, you have to keep buying replacement water filters because you can't clean them like you can the ultrafiltration membrane. You'll know it’s time to flush the ultrafiltration membrane when there is a drop in water pressure coming from the system. The carbon post-filter (BG-20CS) will need to be replaced annually. This post-filter removes chemicals that due to their liquid nature / chemical structure, cannot be removed by ultrafiltration membrane alone. Coconut shell carbon block is highly effective at adsorbing chemicals such as chlorine, chloramine, THMs (trihalomethanes), VOCs (volatile organic chemicals), MTBE (methane tertiary butyl ether), and more. Why the PS-2000C is one of the best bacteria water filters and worth buying: If you have chemicals in your water, this system adsorbs them to improve the appearance and taste of drinking water. It has an easy to flush membrane filter that lasts 3 - 5 years (or more). Other technology which removes ultrafine contaminants can't compete with this membrane life. In the long-run, you'll save money by not having to replace filters as often.

     

    BG-202BIV Two Stage Whole House Bacteria Water Filtration System

    The Premiere BG-202BIV is a two stage whole house water filter with a 0.5 micron absolute rating "charged" nanofiber cartridge and a 5 micron coconut shell carbon cartridge. This system removes bacteria, cryptosporidium, giardia, parasites, endotoxins, sediment, cloudiness, DNA, iron, manganese, chlorine, taste, odor, chlorine, chloramine, trihalomethanes (THMs), methyl tertiary butyl ether (MTBE), volatile organic chemicals (VOCs), and more. The carbon block filter cartridge also has scale inhibitor for hard water. Compared to the ultrafiltration systems discussed above, the BG-202BIV is 0.5 micron (ultrafiltration purifies to 0.02 micron - note the extra zero!) and the filters need to be changed, not flushed.  

    Why the BG-202BIV is one of the best bacteria water filters and worth buying: It's a reasonably priced whole house water filter that removes bacteria, viruses, cysts and chemicals.

    Top Under Sink Water Filters for Effective Bacteria and Virus Removal

    PS-PURUF Ultrafiltration Drinking Water System

    The PS-PURUF is great for removing bacteria and viruses, and delivers pure water on demand – no storage tank required. By not having a storage tank it means that there is no bacteria growth (tanks are notorious for bacteria growth) and also requires significantly less space under your sink. Back flushing membrane ensures longer water membrane life. When a membrane undergoes a backward flush, it’s pores are flushed inside out to clean it of contaminants. Innovative technology lets you flush (clean) the membrane whenever it gets full of contaminants. Simply turn the valve to flush the membrane (please note that a small amount of water will be discharged while the valve is open). Membrane should be replaced every 2-3 years. High capacity coconut shell carbon block cartridges also removes lead, parasites (cryptosporidium & giardia), cloudiness (turbidity), sediment, offensive taste/odor, chlorine, chloramine, THMs (trihalomethanes), VOCs (volatile organic chemicals), asbestos, and more.

    Why the PS-PURUF is one of the best bacteria water filters and worth buying: It's a reasonably priced under sink water filter that removes bacteria, viruses, cysts and chemicals with zero waste water in the production of pure water (unlike reverse osmosis), and you can flush the membrane when it gets full of contaminants.

    About the author:
    Whitney Special

    Whitney is a water filtration expert with over a decade of experience in the industry. Starting in sales, she progressed to leading customer care and technical product support, and now contributes to product development. With an MBA and an MA in Media Communications, Whitney combines technical knowledge with a passion for helping people understand water filtration.