With all the attention that COVID-19-related companies have gotten over the past couple of months, it's easy to forget that there are plenty of other promising stocks out there to invest in. Although it's true that this pandemic has changed the way many companies do business, there are still tons of companies out there that are thriving during this time.

While the four companies listed below are all quite different, they have one thing in common: You've likely forgotten about their stocks due to this coronavirus situation. Let's take a look at just why you should consider adding these four companies to your portfolio going forward in 2020.

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1. Insulet

At present, there are about 425 million people around the world living with diabetes, a figure that's expected to grow to 629 million by 2024. It shouldn't come as a surprise that demand for diabetes-related products will also increase as well.

Insulet (NASDAQ:PODD) is one of the leading insulin pump manufacturers on the market. Insulin pumps are small medical devices that automatically deliver small doses of insulin into the body. While not all diabetes patients need to use insulin pumps, it's much more convenient than having to manually inject insulin multiple times throughout the day, as is the case with type 1 diabetes patients.

Insulet's OmniPod insulin pump brand has seen tremendous growth over the past year. In Insulet's first-quarter financial results, the company reported $189.7 million in total OmniPod revenue. That's a 32.7% increase from the same time last year, with more than 90% of Insulet's total revenue coming from sales of the OmniPod.

While there are other insulin pump makers on the market, such as Tandem Diabetes, Insulet's OmniPod stands out for a couple of reasons. For one, it's one of the only waterproof pumps on the market. At the same time, being tubeless, it can be discreetly worn beneath clothing without anyone noticing, something that can't be said for most other insulin pumps on the market.

2. Editas Medicine

Gene-editing is another sector in the world of biotech that has major potential to disrupt the norms of healthcare, although most companies in this market are relatively small and still in early stages of clinical development for their programs. Editas Medicine (NASDAQ:EDIT) is one such company that has a lot of potential with its own lineup of gene-editing drug candidates.

Editas's flagship candidate, EDIT-101, targets a rare type of childhood blindness called leber congenital amaurosis (LCA), which affects the retina's ability to detect light and color. Although quite rare, affecting about 2 newborns per 100,000, there are almost no treatments available for this condition, and relatively little that can be done once it's diagnosed in a child. The only treatment on the market is called Luxturna, and it is only effective for a very specific type of LCA that only a minority of patients are diagnosed with.

Back in March, Editas announced that it had begun testing EDIT-101 in a phase 1/2 clinical trial with 18 human patients.. Although Editas has a number of other candidates in development -- such as its sickle-cell-disease treatment, EDIT-301 -- what makes EDIT-101 so promising is its lack of competition. While there tends to be plenty of overlap between gene-editing companies and their candidates, Editas is one of the only businesses in this sector working on an LCA treatment at this time. Considering that Luxturna costs about $700,000, EDIT-101 could end up making Editas a lot of money should its clinical trials turn out well.

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3. Pan American Silver

Depending on whether you follow mining-related news, Pan American Silver (NASDAQ:PAAS) may or may not be a company you've heard of before. However, like most gold and silver miners, Pan American has been enjoying remarkably high prices for precious metals thanks to the uncertainty surrounding the global markets.

While gold and silver both have some industrial use, most of their demand comes from cautious investors looking for a place to store their money. That's because prices for precious metals tend to rise as fears surrounding the economy get worse.

This is great news for mining companies, as higher prices mean larger profit margins. When looking at Pan American's most recent fourth-quarter financial results, revenue came in at $404.4 million. That's more than double the $173.4 million reported during Q4 2018. Net earnings are now in the positive as well, sitting at $51.7 million, compared with a net loss of $63.6 million a year ago.

Pan American also finished the acquisition of Tahoe Resources, which included the rights to one of the largest silver mines in the world, the Escobal project. While the mine is currently inactive due to COVID-19 as well as a pending consultation regarding neighboring indigenous communities, Pan American's silver output is expected to drastically increase once it starts operating once more.

4. Trupanion

Insurance might not sound like a super-exciting industry, but it's easily one of the most resilient sectors in the economy. Even better, there are some specific areas of the insurance industry that are reporting compelling growth.

Trupanion (NASDAQ:TRUP) is one of the only insurance companies dedicated to providing insurance to pets. While it's easy to think that pet owners have always considered their animals to be like family, that wasn't always the case. People are spending more money now than ever on taking care of their furry friends. In 2018, the U.S. pet industry grew to $72 billion, well more than double the $29 billion seen in 2001.

As such, demand for pet health insurance has been surging, with Trupanion's quarterly revenue figures having grown exponentially over the past 10 years. Quarterly revenue for Q1 2020 came in at $111.3 million, an impressive 28% increase from the same time last year. The only mild downside to Trupanion is the fact that it's still operating at a very slight loss, about $1.1 million for the first quarter.

Overall, Trupanion seems poised to see steady growth well into the future. While it's hard to find companies that are both recession-resistant and growing rapidly, Trupanion seems to be one of the few stocks that qualifies.